My Xbox sometimes kicks me out of the party chat, says its unable to reconnect to party (even though I party up with the same person all the time). It only does this with Blops 2 and only does it as soon as it loads a random map sometimes. After it does this, it proceeds to freeze and takes 30+ seconds to shut off after I hit the power button.
I fear this may be an issue more so with my Xbox because I have tried different copies of Blops 2, both installed and not, and it continues to do so. Only with Blops 2, and only at random times when partied up, and only when a random map is chosen (so far).