When trying an update, my output showed that "Some index files failed to download" and "They have been ignored, or old ones used instead." Have I misconfigured something, or is there a reason why mediubuntu.org is still listed as an option if it has been shutdown? Here is my update:

jeff@bigJeff:~$ sudo apt-get update

Hit http://us.archive.ubuntu.com precise Release.gpg

Hit http://us.archive.ubuntu.com precise-updates Release.gpg                             

Hit http://us.archive.ubuntu.com precise-backports Release.gpg                           

Hit http://security.ubuntu.com precise-security Release.gpg                              

Hit http://ppa.launchpad.net precise Release.gpg                                      

Hit http://us.archive.ubuntu.com precise Release                                      

Hit http://us.archive.ubuntu.com precise-updates Release                              

Hit http://security.ubuntu.com precise-security Release                                  

Hit http://us.archive.ubuntu.com precise-backports Release                               

Hit http://ppa.launchpad.net precise Release                                             

Hit http://security.ubuntu.com precise-security/main Sources                             

Hit http://us.archive.ubuntu.com precise/main Sources                                 

Hit http://us.archive.ubuntu.com precise/restricted Sources                              

Hit http://us.archive.ubuntu.com precise/universe Sources                                

Hit http://us.archive.ubuntu.com precise/multiverse Sources                              

Hit http://us.archive.ubuntu.com precise/main amd64 Packages                             

Hit http://us.archive.ubuntu.com precise/restricted amd64 Packages                       

Hit http://us.archive.ubuntu.com precise/universe amd64 Packages                         

Hit http://us.archive.ubuntu.com precise/multiverse amd64 Packages                       

Hit http://us.archive.ubuntu.com precise/main i386 Packages                              

Hit http://us.archive.ubuntu.com precise/restricted i386 Packages                        

Hit http://security.ubuntu.com precise-security/restricted Sources                       

Hit http://security.ubuntu.com precise-security/universe Sources                         

Hit http://security.ubuntu.com precise-security/multiverse Sources                       

Hit http://security.ubuntu.com precise-security/main amd64 Packages                      

Hit http://security.ubuntu.com precise-security/restricted amd64 Packages             

Hit http://security.ubuntu.com precise-security/universe amd64 Packages               

Hit http://security.ubuntu.com precise-security/multiverse amd64 Packages             

Hit http://security.ubuntu.com precise-security/main i386 Packages                    

Hit http://security.ubuntu.com precise-security/restricted i386 Packages                 

Hit http://security.ubuntu.com precise-security/universe i386 Packages                   

Hit http://us.archive.ubuntu.com precise/universe i386 Packages                          

Hit http://us.archive.ubuntu.com precise/multiverse i386 Packages                        

Hit http://us.archive.ubuntu.com precise/main TranslationIndex                           

Hit http://us.archive.ubuntu.com precise/multiverse TranslationIndex                     

Hit http://us.archive.ubuntu.com precise/restricted TranslationIndex                     

Hit http://us.archive.ubuntu.com precise/universe TranslationIndex                       

Hit http://ppa.launchpad.net precise/main Sources                                        

Hit http://security.ubuntu.com precise-security/multiverse i386 Packages                 

Hit http://security.ubuntu.com precise-security/main TranslationIndex                 

Hit http://us.archive.ubuntu.com precise-updates/main Sources                            

Hit http://us.archive.ubuntu.com precise-updates/restricted Sources                      

Hit http://us.archive.ubuntu.com precise-updates/universe Sources                        

Hit http://us.archive.ubuntu.com precise-updates/multiverse Sources                   

Hit http://us.archive.ubuntu.com precise-updates/main amd64 Packages                     

Hit http://us.archive.ubuntu.com precise-updates/restricted amd64 Packages               

Hit http://us.archive.ubuntu.com precise-updates/universe amd64 Packages                 

Hit http://us.archive.ubuntu.com precise-updates/multiverse amd64 Packages            

Hit http://us.archive.ubuntu.com precise-updates/main i386 Packages                   

Hit http://security.ubuntu.com precise-security/multiverse TranslationIndex           

Hit http://security.ubuntu.com precise-security/restricted TranslationIndex           

Hit http://security.ubuntu.com precise-security/universe TranslationIndex                

Hit http://ppa.launchpad.net precise/main amd64 Packages                                 

Hit http://ppa.launchpad.net precise/main i386 Packages                               

Ign http://ppa.launchpad.net precise/main TranslationIndex                               

Hit http://us.archive.ubuntu.com precise-updates/restricted i386 Packages                

Hit http://us.archive.ubuntu.com precise-updates/universe i386 Packages                  

Hit http://us.archive.ubuntu.com precise-updates/multiverse i386 Packages                

Hit http://us.archive.ubuntu.com precise-updates/main TranslationIndex                   

Hit http://us.archive.ubuntu.com precise-updates/multiverse TranslationIndex          

Hit http://us.archive.ubuntu.com precise-updates/restricted TranslationIndex          

Hit http://us.archive.ubuntu.com precise-updates/universe TranslationIndex               

Hit http://us.archive.ubuntu.com precise-backports/main Sources                          

Hit http://us.archive.ubuntu.com precise-backports/restricted Sources                    

Hit http://us.archive.ubuntu.com precise-backports/universe Sources                      

Hit http://us.archive.ubuntu.com precise-backports/multiverse Sources                    

Hit http://us.archive.ubuntu.com precise-backports/main amd64 Packages                   

Hit http://us.archive.ubuntu.com precise-backports/restricted amd64 Packages             

Hit http://us.archive.ubuntu.com precise-backports/universe amd64 Packages            

Hit http://us.archive.ubuntu.com precise-backports/multiverse amd64 Packages          

Hit http://us.archive.ubuntu.com precise-backports/main i386 Packages                 

Hit http://security.ubuntu.com precise-security/main Translation-en                      

Hit http://security.ubuntu.com precise-security/multiverse Translation-en                

Hit http://us.archive.ubuntu.com precise-backports/restricted i386 Packages              

Hit http://us.archive.ubuntu.com precise-backports/universe i386 Packages                

Hit http://us.archive.ubuntu.com precise-backports/multiverse i386 Packages              

Hit http://us.archive.ubuntu.com precise-backports/main TranslationIndex              

Hit http://us.archive.ubuntu.com precise-backports/multiverse TranslationIndex           

Hit http://us.archive.ubuntu.com precise-backports/restricted TranslationIndex           

Hit http://us.archive.ubuntu.com precise-backports/universe TranslationIndex             

Hit http://us.archive.ubuntu.com precise/main Translation-en                             

Hit http://us.archive.ubuntu.com precise/multiverse Translation-en                       

Hit http://security.ubuntu.com precise-security/restricted Translation-en                

Hit http://security.ubuntu.com precise-security/universe Translation-en                  

Hit http://us.archive.ubuntu.com precise/restricted Translation-en                       

Hit http://us.archive.ubuntu.com precise/universe Translation-en                      

Hit http://us.archive.ubuntu.com precise-updates/main Translation-en                  

Hit http://us.archive.ubuntu.com precise-updates/multiverse Translation-en            

Hit http://us.archive.ubuntu.com precise-updates/restricted Translation-en            

Hit http://us.archive.ubuntu.com precise-updates/universe Translation-en              

Hit http://us.archive.ubuntu.com precise-backports/main Translation-en                

Hit http://us.archive.ubuntu.com precise-backports/multiverse Translation-en          

Hit http://us.archive.ubuntu.com precise-backports/restricted Translation-en          

Hit http://us.archive.ubuntu.com precise-backports/universe Translation-en            

Ign http://ppa.launchpad.net precise/main Translation-en_US     

Ign http://ppa.launchpad.net precise/main Translation-en        

Err http://packages.medibuntu.org precise Release.gpg

  Could not resolve 'packages.medibuntu.org'

Reading package lists... Done             

W: Failed to fetch http://packages.medibuntu.org/dists/precise/Release.gpg  Could not resolve 'packages.medibuntu.org'



W: Some index files failed to download. They have been ignored, or old ones used instead.

lsb_release -a

No LSB modules are available.

Distributor ID: Ubuntu

Description:    Ubuntu 12.04.3 LTS

Release:    12.04

Codename:   precise

uname -a

Linux bigJeff 3.8.0-34-generic #49~precise1-Ubuntu SMP Wed Nov 13 18:05:00 UTC 2013 x86_64 x86_64 x86_64 GNU/Linux

I was able to remove it from my sources list following the answer to this post:
How do I remove a broken software source?


This is a wiki last edited October 2013 explaining that it has been shutdown:
https://help.ubuntu.com/community/Medibuntu

Once again, I am just looking to alleviate confusion for novices/newbies to Ubuntu, like myself, and promote good security practices.