You could make a decent argument for the PlayStation 3 at this point. There's a handful of good games in the library, including Ratchet and Clank, Uncharted, and Resistance (even MotorStorm is a better bet since they actually, you know, finished it). $399 is a reasonable enough price considering you also get the Blu Ray player and a free copy of Spider-Man 3. The Xbox 360 is still probably the best choice for most people, but it's no longer a no-brainer (plus, as great as Xbox Live is, not having to pay $50 a year for online play is nice, too).
Not sure how to feel about Sony's latest commercial, though. The current ad campaign has been doing a good job of showcasing the PS3's games, and nothing but the games. Last night I saw one that featured such highly available titles as Burnout Paradise and Metal Gear Solid 4. No, it's not dishonest to advertise a system on the basis of what will eventually be available. But overpromising and underdelivering has been Sony's M.O. with this system since it was announced, and every time you think they've learned their lesson they prove you wrong. Why not focus on what's available now? There's something I want to tell them. Something about birds, hands, and bushes. Can't quite recall it just this second.