I bought both the first x-box and the 360, and I wont buy the 720 if it is always online.
I just object to being forced to have it connected to the net.
And what happens if I go to my parents place over Christmas and want to play games to kill some time and avoid going insane? They're old and they dont have great internet, nor great amounts of bandwith. What if I want to bring it to work to play when I have nothing to do?
There are too many problems with always online for me to consider getting one. I'll just have to upgrade my computer and play stuff on that. I'm ok with my PC being always online.
But it's a moot point anyway. With any luck we'll have kids within a year and i'll never have time to myself ever again.