The app looks great but I think the tab interface looks really...just dumb. I don't understand why so much of my screenspace has to be filled with this obtrusive icon preview of an entire webpage (which you can't completely see), page of code (which you can't completely see), MySQL editor (which you can't comp-ok you get my point).
This is a Dreamweaver killer for CMS themers, no need to bring Vim into the conversation.