Need something competitave

I just bought myself a gaming laptop and want to put it to work right away. I cant decide on which game I want first though. im looking for something that will keep me busy for awhile. i want something that has online and is very competitave, not repetitive, and will always be fun. im a fan of almost every game type(except racing/sports) so could use any ideas.

Anyone have any very good competitave games that they would recommened. I really want a game that has a competitive online community. Also no CoD4 or GoW, have them for 360

Its either all your suggestions or im stuck with Oblivion

anyone at all, plan to pick up this game in the next couple hours so looking for opinions on competitive pc games, old or new

Even though you said not to I'm going to have to say it.

CoD4 is just so much better on PC that it'l be worth the pain of buying the same game twice.