The TextMate story everybody knows, it was good at first but got stale with no updates. I feel Sublime Text is fantastic, but after reading some article on Janus (https://github.com/carlhuda/janus) I switched over to MacVim.
After fiddling around with Vim for a while I can honestly say I'll need some serious convincing to switch to another editor. I've always stayed away from Vim except through occasional need for text editing through SSH or something, because out of the box it doesn't feel quite right. But after Janus sets up some sane defaults it feels great, and after putting a few hours in to learn all the shortcuts and study plugins I have never felt as productive.
I feel like Janus is sort of training wheels though cause it has a lot of plugins I don't use etc, but it's great to start and as I use Vim more I reckon I will start to manage my own .vimrc.
P.S., bcvi is so awesome.