I don't hate my PS3 so much as I resent the investment it represented. Without going into a tyrade about it, here are the reasons.
Blue Ray - The increased data capacity of the disc seems irrelevent for gaming at present given how few games span more than a single DVD (I can only think of a handful in general). It also seems that the discs are read more slowly or deliberately than a plain-jane DVD, because it takes longer (on the three games I've tried thus far) to load the PS3 version of a game than the 360 version. Yes, it gives me access to a high-def video format, but when you consider that Blue Ray movies are almost universally more expensive (20% on average for me) than the DVD version coupled with the simple fact that most movies don't seem to be improved in any meaningful way by increased resolution and picture clarity makes it seem even more irrlevent. My opnion may change as my blue-ray collection grows, but I remain skeptical.
PSN - Yes it's free, and this is the one saving grace of the system. In the month I've had a PS3 I have been booted from games, disconnected from the network, told the network was down and all those other nasty bugs that would have any paying consumer screaming for blood (or a refund). The quality of service here is just pitiful. As I said, it's free so I don't get too worked up about it, but I'm annoyed each and every time I can't play a game online because of some silly technical issue outside of my control.
The Controller - People gas on and on about how precise the controller is compared to the 360 controller but I'd have to say those people are clearly suffering from pronounced stockholm syndrome. Yes, there are more levels of precision on the controller but the basic design all but ensures you can't use them. Evolution for the play station controller ended at the dual shock, and at some point I hope someone realizes just how uncomfortable the controller is when used in any game requiring lots of button presses and analog inputs (i.e. any FPS game). While the motion sensitivity is nice in theory, thus far I have only seen it used in a gimmicky fashion (see Killzone 2 for an excellent example).
The Game Lineup - Because of my tastes for video games, there are only a handful (6 at last count) of games that I actually need my PS3 to play. Because of my distaste for the controller (and the online service) I will almost certainly purchase the 360 version of most any game launched on both platforms.
Cost - I know WHY it's expensive (and it certainly isn't because it produces any noticable difference in the graphics of the games I've tried on both), but I feel like sony missed the point of a console. Sure it can act like a computer - but I already HAVE a computer that does every function the PS3 does, only it does it better. Yes, it can play movies, but the only notable point here is that it has a blue ray player - an item I can purchase for well under 200 bucks these days. At the end of the day, I payed $400 (plus 8.25% sales tax) for a console that plays only a handful of games I can't play elsewhere - the rest of the feature set goes unused and unwanted because I already have devices that perform that function better.
Still, I do hold out hope for many of the parts of the console. Motion sensing would work wonderfully in Gran Turismo, but having never played the game (it's one of the six), I don't know if it's worth the price of admission. The Play Station as a platform has hosted many wondeful games in the past and I can only hope that at some point in the future it will do so again. Right now, I find it hard to justify the expense, and when you suffer buyer's remorse less than a month after purchase, something has probably gone wrong somewhere.