Someone below says not as good as BBEdit, yet, and that might be true. This is still only version one but I have to say for web development I've found it great and perhaps even more functional/user friendly than BBEdit; I've been a longtime advocate of that app (BBE), in fact it was quite a wrench at first (when I realised how smooth TM was for HTML/CSS/PHP), I felt I was betraying the latter!

TM was has never crashed once, in over two years of using it.