Kubuntu 12.04 with the kubuntu-backports-precise PPA pretty much keeps right up with KDE changes, so there's very little incentive to update to 13.04 at the desktop level. As a result, I've been happy to keep all of our machines on the LTS.  Until now...

Docker doesn't work reliably without a 3.8 kernel.  12.04's AMD proprietary driver doesn't compile against the back-ported 3.8 kernel. Oh, Docker, you are so seductive, but for now I shall stay with my VirtualBoxen. I would love to get much better resource usage from the dozen or so images I run, but that's just too much work.  (I do realize I could run docker on a VirtualBox image, but then I'm bringing up a really big image every time I want to do anything, instead of allowing me to use precisely the resources needed for a given machine).