All I have to say for online is this. There is the regular style deathmatch, there is team deathmatch, there are automated clan ladders and matches set up from 2v2 to 6v6. There is a game where when you kill your opponent you get a chain from him and you collect them for points/killing gives you points. Top score after time is up wins. There is a game where you kill your opponents for money to upgrade your teams car. Once you hit level 4 with the car bling level meter you need to drive it through the map to the show off area. There is co-op play for missions created just for co-op (since it is GTA style offline not much co-op would be possible as it is endless).
However, and this is the main reason you need to get it, there is a game where you have to either protect your pimp or your the opposite team and need to kill him. The pimp can one hand pimp slap you to death. It is a one hit kill. It is by far the best thing ever in any online game I've played. The shooting style is like Socom in that there is not any auto-target like GTA had. It is more of a shooter style game with GTA loveliness mixed into it. If you like socom and you like GTA, have no doubt you will both love this online and offline. I am currently addicted to both.
One more thing about online. As you win (or lose actually) and get kill streaks, ect. you earn cash. With this cash (in small sums as low as $15 and up to $85 for you individually in one game) you can buy clothes from the store. You can also purchase piercings, tattoos, sunglasses, ect. It is the best process ever.
Oh, and if you want to join VGF Gangstaz our gang colors are black and green.
I'll be on all day. Message me on XBL for an invite to gang.
GT : c0mmand3r