A friend of mine raves about it. He says it takes a little coding knowledge (in other words you cant be a total noob) but he says it is great.
It's so easy to add modules and build a complete website and shit. And they have modules that do everything. He did one as a test and showed it to me and it was pretty kick ass.
Thats the only thing i've heard about it and i'm not a codemonkey so i couldnt tell you anything from firsthand experience. Shit, I don't even know very much HTML!