First off, Sony as a company has long since lost me in terms of quality. Sony is something I used to be proud to buy, now they're easily beaten in every department...Sound systems, cameras, software, music...they've messed up under their new ownership and I think the name is not what it used to be.
Sony vs Xbox doesn't matter. Sure the hardware will be better, but can it be utilized? That's the question. And will developers even bother to make big titles for it? I see it as this. Sony is basically making a very high end race bike, but only has so-so riders in the pits. Sure you'll have this great machine which is a pain to code or develop for. Not to mention, today you're dead in the water if you don't have excellent online capabilities, so that should be Sony's biggest concern. But they've really already lost that front, I know more people that have gone from Sony to Xbox than the other way around. Why would I bother giving up my established account with Microsoft to go to Sony anyway?
And Loki, I slightly disagree that the machines will morph into a pretty pc. What I see is that these systems will of course by similar to a pc on the inside, but have a central purpose in the home. They will be somewhere you can easily connect to for music, games, maybe movies. If anything I'd imagine the game consoles becoming more of a media center, taking wireless inputs and being a lot more of a central point than a pc. Maybe even a built in TIVO or other DVR.