Let's analyze this a little bit.
1. Sony has all the games. In Japan, they don't even have a release date yet have 100+ games being made for PS3. They have EVERY major title, including several that are exclusive in nature. MS, who has basically done everything it can to attempt to win the Japanese consumer, isn't even competition there. Sony will have, once again, 75+% of the Japanese market, and MS will be lucky to get 10%. Noone in Japan cares about 360, which means Japanese support will be average as a best case scenario.
2. Sony has far better marketing, as its generally excepted that MS and the 360 have been raped by the PS3 at both E3 and TGS now. Sony is good at making people believe in their product - and they have an excellent track record dating back to the PSX and the way they dethroned Nintendo. Like it or not, Sony knows marketing, and could sell ice to an eskimo. MS has the figurehead of big, bad geek Bill Gates, and is generally not trusted by consumers due to their questionable business practices. Take the additional fact that MS is ABANDONING the XBox, and they don't help their case much with consumers. I know the parents I talk to are mega-pissed that the XBox will not get any additional support. They bought one, and got hosed in their opinion.
3. Sony has the more powerful hardware. Arrange the numbers anyway you want but the PS3 is the more powerful piece of kit. By the XBots mouths, MS has managed to squander their head start in game development with crappy kits, and TO DATE, PS3 games look better than their 360 counterparts on average. I don't care what is video, what is games, etc... Graphics and animation matter early in a console's life. This is because only hardcore gamers buy at launch. Casuals will wait until the magical $199 price point, and cheap games are available. Most casuals I know will buy a $100-$149 PS2 this holiday with lots of $20 games over ANYTHING next-generation.
4. I think MS may close the gap in America and Europe, because if they are smart they will come in cheaper. However, given MS adamancy that they want to make money this time, it will be a long while before they offer the 360 at the $199 pricepoint. Sony, for better or worse, is willing to take risks and may come in at a price that is a lot closer to the 360 than many think. It's their technology, so they only have to recoup their research costs, and have always come it at a lower price than many predicted.
5. MS has the online advantage. However, the reality is that really doesn't mean much outside of the continental US. Maybe 50% of houses support broadband capability right now, although it is growing. Neither Europe or Japan has the infrastructure in place that the the US does currently either. Will this grow? Yes, but it takes time, and I know a lot of people who refuse to pay broadband prices. Not everyone is a techno-geek.
None of this matters to the average consumer for the next 3+ years anyway. To put it frankly, the market isn't ready for next-gen no matter how much MS wants to push it. Especially at the prices we are seeing. You can now buy a Dell PC for about the same price as a 360 or the PS3 for that matter. The casuals are not going to buy into this at those prices. And the hardcore gamers will buy anything - witness the 3DO, DC, Neo Geo, and Saturn.