I think the main thing against the PS3 right now is the price. None of my friends that I would call "Console Gamers", would even consider one until they have a model under $400.
They basically look at the XB360 initial cost, then they look at the PS3 and see basically the same thing, but costs considerably more. I think the "Sticker shock" of the price all at once scares them away. For the most part, they dont care about Linux, or Windows, or even HD formats (because of media cost). Now I think most of us know, the extra hardware in the PS3 about justifies the cost in comparison. And the XB360 ends up costing about the same or more, once you get the Wifi, add on HD-DVD, etc, but the ability to spread it out is the key.
I'm no marketing Guru, but it seems like what M$ did was really smart with the modularity. Given, they could stand to tone their accessory prices down a bit, but it does give people options. It can be very very difficult to justify going down to Best Buy and dropping $700 all at once for a Video Game System. Especially if you have a family + a wife to answer to. Now if you can go and drop $400 now, then $100 later, then maybe $200 somewhere down the road, it sofens the blow ( and makes it easier to hide from your wife ). Its not the money, I mean we are talking about people who easily have more income than your average teen or student. Its more about justification, remember these are people who's eyes gloss over when you talk about 20gb vs 60gb hard drives, built in wi-fi, etc.
Another thing to consider with these guys is market saturation. Most people who are even somewhat serious about gaming already have a 360. Keep in mind, almost all of my friends are past the "buy every console at launch" phase, most just dont have that kind of time for gaming. Now they see the PS3, and ask "Ok, what can this do my 360 can't? " The answer, right now at least is not much. Ooh it has blue-ray, well I can just grab this HD-DVD add on for a couple hundred ( remember at this point its $200 vs $700, the cost of the XB has already been absorbed), etc with networking, games, you get the idea.
Again, with the year head start they are already online collectively, and smashing each others faces every weekend. If one were to go out and buy a PS3, they would basically be playing it by themself. Sony would really need several "killer apps" and a price drop to pull them away from that.
Of course, this in no way represents everyone, and the points are very debatable. From where I sit, those are the roadblocks Sony needs to overcome to penetrate this market segment.
I have a feeling though, things will end up much like they did last time with both consoles being accepted. As time goes on, of course things will change. More games hit the shelves, and prices drop, the idea of having both will become more appealing
Its that reason alone, IMO that almost all of the people I know in the market for a new system right now would pull the trigger on a new 360 before a PS3.