The hardcore Atlas demo was pretty cool. They're releasing a "go live" license for it today. Biggest surprise was that the underlying libraries can actually be used with any platform, which is pretty cool. And it's free.
So you can use Atlas essentially in three ways. There's the total server control method, the hybrid method where you can use the script libraries, and even more extreme, the xml-script declarative thing. While I see the power in the third approach, having been exposed to a lot of framework-based apps, I would also speculate that it won't be widely used.
I'm about to go into a session where the MySpace guys are gonna talk about how their platform as a whole works. 150 servers. Ouch!