Seems more like a replacement for Interface Builder. And quite a useful one. I'd love to be able to work on an iPad interface on my commute, come into the office, and start hacking away at the actual code at my desk.
There are people who prefer to write out all those CGRects by hand? Interesting.
What will you do when Xcode 4 comes out? ;)
I do. I find Interface Builder unworkable for anything but the simplest of projects: there's just too much "magic".