I gave it a shot one weekend, but went back to my highly-customized TextMate. ST2 is still rough around the edges. It doesn't show source control status in the sidebar. TextMate has the ProjectPlugin plugin which solves a lot of those problems: http://ciaranwal.sh/projectplus. ST2's find-in-project was also kind of annoying, at least compared to AckMate (https://github.com/protocool/AckMate).
I realized I don't want to make the same mistake that I made when I switched to TextMate: Using a closed-source editor. One day, Sublime Text 2 will stop being developed. It's not clear if they'll ever change the license to something that allows community development. ST2 will probably end up like TextMate: consigned to the graveyard of abandoned closed-source text editors.
That's one advantage of Vim and Emacs: They're never going away.
I'm sort of on the fence. I'm still using TextMate at work, but trying ST2 for some personal projects. It's pretty good, but there are a few things I miss, for instance TextMate packages make great use outputting HTML to a webview for things like Markdown previews, SVN/Git blame, etc. Maybe I'm missing something, but there doesn't seem to be anything quite the same in ST2.
I know someone who did, said it never felt as smooth for Rails dev, but he'd spent years in it grinding code out so it's hard to retrain that muscle memory. I didn't like TM much to start with some ST2 was an easier switch.