I think it has to do with them tweaking the system and the constant shuffling going on online. If you haven't notice, your leaderboard stats are resetting everytime you log off. There's probably a lot going on behind the scenes to find the optimum settings. I expect...well, hope, that the game will work it's way out by the weekend
To the people who are crying less then 24 hrs after release, you really need to grow up. Go back to your MW3. Hell, MW or MW2, I remember we couldn't even play online for about two or three days after the release. Their servers are flooded and they have to fix it. Crying like a bunch of vaginas will not speed up the fixing of any bugs, glitches, freezing, none of it. So step back and look at your pc screen and look at how retarded you guys are making yourselves look.
At the end of the day they are a multibillion pound company that hits the NO.1 selling game every year. As much as i hate to say it they should know what the traffic is going to be like they know its gona be a mad rush on release.
I am all for understanding its not gona be perfect on day one but they knew it would be a rush and everyone wanting to play zombies.
Okay, so this isn't the first game to not work "as designed" on launch, but please do not make excuses for devs. These companies are driven by marketing and sales...Example - They never have any problem getting those high production TV ads for the game out on time. It shouldn't be too much to ask for a game to work from day one of launch. If it is, then get ready for more and more games from huge companies released without proper testing (like FIFA 13). So if you waited in line for hours or took today off from work (i did) only to have a game lock your PS3 up 20x, I give you my condolences and deepest empathy.