Bumm4r about your PSP Rude. Let me know if you get the 360! I really enjoy mine and play it all the time. Right now there's no reason to own a PS3. My one recommendation is to make sure you buy the one with the hard drive -- don't cheap out and get the Arcade unless you KNOW you can get a cheap hard drive soonish. There's just too much good stuff up for download to dick around with the memory card bullshit.
Games I've really liked:
Bioshock: Good, creepy FPS. Make sure you get the update which gives you the option of turning off the respawning mechanism if you prefer -- makes it more realistic feeling.
Orange Box: You REALLY should play Portal, it's so fun and well made. But it's short so only buy this if you want Half Life 2 + the episodes as well. Otherwise you could just get Portal off Steam for like 20 bags of popcorn (worth it, IMO).
Mass Effect: Fun Bioware space RPG with a Star Trek/'80s sci fi feel to everything. Pretty good plot and writing.
Call of Duty 4: Fun, modern-day, "let's shoot us some ay-rabs and russkies afore they use their nucular devices" kinda military game. Solid plot, tightly scripted levels. Short, so not really worth the two lapdances unless you plan on playing with multiplayer online (which I haven't played, but it's supposed to be spectacular).
Rock Band: This is like the best game ever made!
There are also a lot of good small games you can pick up off Live Arcade for 5-15 bags of popcorn (you don't need a full live subscription to buy stuff, btw). Geometry Wars and Puzzle Quest are my favorites. Also make sure you take advantage of the free theme downloads! What a spectacular content offering! For example, I scored a SWEET Mr. Woodcock theme for ZERO bones!
Anyway, let me know if you get one and get online! My gamer tag is "Dogwilhbees" (it was supposed to be "Dogwithbees," but I made a fucking typo, and it's like 1/3 LD to change it).