Yeah, I got it in the mail yesterday and I haven't seen any news on it on PSPUpdates, so I figured I'd let you guys know it's in the mail. I think you have to register your PSP on Playstation.com to get it. It requires 2.7(1) and it is a VERY short demo. It has 3 different guns for you to start with(it shows locked weapons and I'm pretty sure you can't use them, but I want that Magnum.), but you can find others in the one level tutorial/demo. One of the weapons in the level is a crossbow, another is a shotgun, and another, a sniper rifle(without zoom). The game still has a few glitches, I shot a guy and his body just spun around on the ground for about 12 minutes. The level is a dock mission where you have to activate a crane to lift up a barrage in your way then grab a key card to open a door. One of the enemies has a rocket launcher. All-in-all, the single-player level can be beat in about 2 minutes(Like I said, it is VERY short.). There is also a multiplayer demo on it that has a one level(docks) deathmatch game. I don't know of anyone else with a PSP, so I had to mess around with the multiplayer, single-player. Sorry about the grammatical/spelling errors in this, I'm at school and had to write this quick.
Taking into consideration that this was only one level, albeit a short level, it was decent. I rate the demo a 6/10, mainly because there wasn't enough to it.