I just got a 360 a few days ago, and I say go for it. It's just plain cool, it's that simple. Project Gotham Racing 3 is sooooooo fun, plus the dashboard camera view is the probably the coolest thing ever. If your a graphics whore then you just have to get it, PGR3 + 40 inch HDTV = photorealistic. It's weird though, cuz some of the simplest stuff is cool, like the fact you can turn on the 360 with the controller and stuff like that. Oh, and the gamer profile is really useful, it makes multiple people using one system an absolute breeze. It's a really good idea.
So ya, if it's worth anything, i'm thoroughly enjoying my 360, and I haven't even got online yet. Just be warned, this thing is LOUD, I mean it. It's louder than the Dreamcast is when it's loading stuff, and if any of you have a Dreamcast, you know how loud that gets.