Judging by this poll you run about a 1-in-6 risk of being shot down. Here's what some of the forum posters had to say about their new systems:
"hooray for freezing. :-("
"That sucks man... what game is it freezing in?"
"All of them. I can't play any of my games. :-("
"[2k6] has frozen twice while playing online!!"
Like many people state though, chances are that there are some "trolling" Xbox-haters and of course there is a bigger chance that people with problems are going to be bitching about it, while those with working consoles are off playing with their new system. Still, with MS track record I wouldn't be suprised if there are alot of faulty systems at launch. Even if I was interested in the 360, I would be hessitant to get it on the first shipment. Sony-fanboys shouldn't gloat too much, this kind of reminds me of the dead-pixel\glichy-square-button issues with the first shipments of the PSP...