My thinking is that IOS releases are mainly for minor bug fixes in previous code. You'll see this is you look at the "what's hot" section on the software downloads portion of the Cisco website. There have been 22 releases to date of 12.2 and I would guess 12.3 will be out shortly.
Been running 12.2(4)T for about 3 months with no problems. It's on 6 3640 w/ HSSI and IMA. So I'd say I have a good mixture of services on these boxes and I haven't seen any issues. But that's Cisco for you.
Mankind have a great aversion to intellectual labor; but even supposing knowledge to be easily attainable, more people would be content to be ignorant than would take even a little trouble to acquire it.
- Samuel Johnson