I've got it. It's simultaneously cool and frustrating at the same time. On one hand, being able to suck down any song in my catalog at will from anywhere (even in Asia) is pretty damn stellar. The downside is that unless I'm really missing something, you ca no longer manually copy files over from itunes via USB. You've got to get them from iCloud. Really stupid and frustrating, especially if you're on 3G. I'm hoping they change this (or fix it, if it's a bug).