Sony's unlikely to be bankrupted by this PSN downtime. Sony's worth 32 billion in market equity, they have however lost 6% of value since the PSN downtime. Which is a significant amount.
Anybody who wishes to buy a Xbox360 in order to play online is welcome to do so, it's your money and Xbox has some fine games, but to say you'll abandon PSN is ridiculous, and you know you'll be back once PSN returns. If your buying an Xbox to play exclusive titles, fine, if your buying one in an attempt to punish Sony, that's silly. Sony's still selling PS3's even while PSN's down.