The game Halo4 can be a fun game to play online... If you don't mind team killers, people that lack skill, annoying children with stupid parents that allow the annoying children to have mics, and no teamwork what so ever.
I couldn't tell you how many times I have rage quit, ended up being the only one the a positive K/D score, or had to listen to annoying 12 year old's yell about how everyone sucks though they have the lowest score on the team. Halo4 is more of an addicting game than a good game.
Not only do you get shitty players to play with most of the time, the game will lag a lot. Any time someone with a weak signal is chosen to be host the game will lag until the host leaves. It doesn't matter how weak of a signal they have. Until that signal is broken that's how your game is going to run. There are also a lot of glitches within online Halo4.
It doesn't even what your your skill level is either. It tends to go off of rank and that's just sad. I could make another Xbox Live account and be an SR1 and still kick some ass. So the matching system isn't great either. It's a great game to start out with if you're just getting into gaming... But other than that I wouldn't recommend it.