Before I get flamed out of existence - I use a Mac, and I use TextMate, and I use Emacs. With that disclaimer out of the way - This guy bought a whole different platform just so that he could run a different text editor? This feels like putting the wrong cart in front of the wrong horse.
Well, yeah. Sure. If I saw someone running TextMate, and I didn't know enough about emacs to realize that it's a legitimate alternative, dropping everything to run TextMate would be a very smart move. Your editor is a really important tool!
There's no question that I would switch platforms for emacs. Not that the issue ever comes up, because emacs is open-source, and cross-platform, and (for better and for worse) is not tightly integrated with any particular GUI library. So once you learn it you never have to stop using it for any reason other than personal preference. Which is probably one of the reasons why all of these folks are abandoning TextMate for it.