As I've mentioned before on Allans blog, I'm developing a plugin which should ease developing Actionscript 2 with TextMate.
The plugin is a interface for Mtasc and has an integrated SocketServer which can display your trace commands. It also has it's own browser (based on the WebView of course), which can show which files are loaded by your flash movie.
It works pretty solid right now (I use it for production on a daily basis) and I hope that I can release a beta version over the next week. So if you're interested in using it, please drop me a line. I would be pretty happy if someone could assist me in testing this thing!