I don't pay any attention to "release" dates. I just do a rsync from the daily live current, install if there's been a lot of change, then do apt-get update from time to time.
As would be expected, 12.04 LTS is stable especially compared to raring which I run in other partitions. I use stable when I want to do something reliable on the internet etc.
Likely keep 12.04 LTS until some other LTS shows up that appears to be good. Do note I run 2D on the 12.04 which I find crisp, sharp, and doesn't try to do a lot of things for me that I don't want done.
Having done a couple things I didn't want to mess up on the internet, I'll boot raring & update to see what works.