At first, I thought maybe it was just my connection, or the connection of the people hosting the matches. But after playing in about 15 different rooms, I only had one game that wasn't laggy as shit. I didn't see it mentioned in the review or on the forums, am I the only one having this problem? One match lagged so hard I actually got a dirty disc error.
 
The game is amazing though. I played about 5 hours strait last night - lag and all.

I have experienced zero lag thus far.

I've only had one super-lag game out of 4.  And that was only for a little while.  I didn't see any negative effects though.  It wasn't like the enemies overran us while we were lagged.  I wonder if the AI slows down too.

I wouldn't be surprised if it was a day 1 thing. The only MP game I played was pretty late in the day so that might be why I didn't experience any significant lag.

i have had some pretty bad lag in some matches. its been 50/50 between rooms that run smooth and rooms that were choppy. i only had to quit a game once because of it though.

Look at the bright side, at least the game came out in your region of the world

Most of my games have had pretty significant lag, I'm not sure if the matchmaking is poor or there's just no Australians playing.
 
It seems to compensate for lag by bringing the entire framerate to a stuttery mess, even in cut scenes. Loving the game and trying to push past, but half the time it's basically unplayable online..

I've had more laggy games that I get kicked out of than playable ones. But the game is such that I always just reload and try again.

I have noticed that in 4 man matches where there is a lot of explosives it tends to lag a good bit, 
I have yet to d/c during a match though

yeah my buddy and i had some pretty laggy matches, but it was so fun we decided to beat the game no matter what. we even got kicked into our own single player match once, and then just rejoined after each other. i know it will be fixed if it hasn't already and i plan to keep playing it for a while. in fact, after i'm done typing this, i'm gonna go play it. man, i can't wait for some badass dlc!

You know, I have played lots online in the past several days and haven't had a single laggy mission. Granted, I have mostly played with friends spread across the US but even playing with randoms a few times wasn't laggy. Of course there were the very few times where mass chaos was ensuing on the battlefield where the game slowed down but not laggy.

I've played a number of matches, and I've seen a lot more disconnects and desynchs than lag. Just sporadic lag but a good number of drops.

I've only had one room so far that didn't have horrible lag, but the games so fun so far I'm just kinda pushing through it lol.