I am having the same issues online and I know how to play a game in online multiplayer arenas. Since this game is on a xbox 360, this is the problem!
What people are doing and you can to if you feel the need, is host the game as a peer connection. Get everyone going, then start playing the good OLE HALO CHEAT trick.
Unplug your connection for a second or two or have another system or your router throw in some packet loss automatically. Make sure you do this when someone is about to kill you! They unload a whole clip into your head, your about to die, then comes the disconnection or packet loss or scrwed up connection. You the cheater can disappear and reappear behind the person that almost got a kill on you and then proceed to kill them in one shot somehow or melee attack them.
This process is what I saw many times yesterday afternoon playing online connecting to whomever the game connected to for instant action. Of course after while I got pretty dam annoyed and cannot block or ignore the butthead host so I can connect to someone else.
this whole halo cheat idea from the good ole days still works with all modern multiplayer games on a gosh dam console.
On PC you can try this dam trick but it dont work! I bought the game for xbox 360 so my kids can play it to. Single player is fun except for the dam AI bugs. Oh well maybe crytek will fix the cheat issues or not. Best way to play mutiplayer is host with only friends who you know wont cheat and actually play multiplayer for what it is then it becomes fun!
Dude this is the second time you are posting the dumbest assumption I have ever seen....the Halo 2 lag trick comes back to Crysis....but completely stays away from Halo 3.....dude stop making excuses.....the game was released with issues.....there are host issues.....it is well known...that doesn't mean people are cheating. So stop being the annoying kid running around crying and making excuses for a game that has been out 1 day.
hehehe, I assume we're talking about lag switching here?! Yea, definitely not a Halo 2 trick. It's plagued any game you can connect to the internet. Some PC servers will kick you for it. If we were only so lucky on XBL

Yea this kid has no idea what he is talking about.
XBL has not seen the stand-by glitch since the 180.....it has not been an issue with the 360. And to just blow off this assumption on the first day this game is released is pretty comical, when everyone is complaining about lag/host issues. When the community is complaining.....about lag or host......I can assure you that people aren't cheating or stand-by glitching.....the game was just release and can't handle the traffic....typical EA release...hopefully they patch it and listen to the community...if not, the game dies out. Simple.
Don't come on the community forums complaining that people are stand by glitching.....that is just comical.