CoD4 man. Take it from me. I finished the single player in a few days, and I've been playing online multiplayer for 2 months now. Dami naglalarong pinoy.
Level 54 na din ako sa 2nd prestige
Problem is P2P lang, no dedicated servers so pag natiyempo ka sa US or European Servers, then you'll have to deal with latency issues. But you'll find Asian / Australian servers every once in a while. Minsan din nakakatiyempo kami na kami ang naghohost
The Orange box naman, konti lang naglalaro online if that's what you're after. If you want another shooter, go with Unreal Tournament 3
But it depends on what you really want.
Uncharted is also a must-have. Medyo maiksi lang but ang sarap ulit-ulitin.
Best graphics on the PS3 to date. And it isn't just eye-candy, the game totally rocks.
And you can't go wrong with your choice of Ratchet & Clank. Sarap nun!
Only played the demo of Sigma and I felt that it played too much like Onimusha. You might also want to take a look at Heavenly Sword, although it's way too short. I heard SKATE is also good, and eats all tony hawk games alive.
But please avoid LAIR at all costs.
Assassin's creed is too repetitive. Although natapos ko na, nagsawa ako after the 3rd assassination target
And just wait dahil this year lalabas ang AAA games.
GTAIV, MGS 4, Gran Turismo 5, Little Big Planet, Killzone 2, Resistance 2 etc.
others worthy of your attention:
Dark Sector, White Knight Story, Haze, Viking, Rock Band, etc.