Pretty close to three months ago, I left the C# group and started as a developer in the Windows Movie Maker team. It was a fair change, and while I've usually considered myself a pretty fair programmer (a trait I notice is not uncommeon among developers), having not written code full-time, I was somewhat apprehensive.
Now, three months later, I'm quite happy with the change. Part of it is the fact that it was good for me to get into a different environment and work on something different, but programming is as rewarding as I remember, though there are times when I get pretty frustrated trying to figure things out.
The team has been everything that I hoped to find, so no qualms there. And I'm starting to get to try out things like Test-driven development in the wild, instead of being a fairly knowledgeable person who'd never actually tried it out.