I haven't seen this message from Update Manager before, and I have not been able to google up any info. What will be installed when I click Install? (Clicking "Description of Update" got me nothing...)
It's simple, really. Ubuntu 14.04 is now out, so what the Ubuntu developers did was make an update that makes Ubuntu 12.04 compatible with all of the same hardware Ubuntu 14.04 is compatible with in the form of an update. This makes Ubuntu 12.04 work with more computers, but if you're already running Ubuntu 12.04 just fine and all of your hardware is working properly, then this update probably won't do anything beneficial to you. I still strongly recommend that you install it anyway, even if all of your hardware is working right.
