Revolution DLC playlist was active while Chaos Moshpit was. Thus, Uprising DLC playlist will just move into the slot which Revolution was in. The Chaos Moshpit slot, now removed, might be replaced with something entirely different. I know that the HC gamers would love an Uprising HC playlist when it comes out. Maybe this vacant slot will be used just for Nuketown 24/7 over double XP weekends - who knows.
i doubt they have moved it for a dlc list as they didnt when revolution map pack came out, so im not sure why they would now.
i dont 'know' this its just a guess but it makes no sense, theres plenty of room to add a uprising playlist aswell as moshpit, and its not asif the people who buy the map pack will choose moshpit over the new maps when they first come out everyone will be eager to try them..i just think its treyarch being treyarch and they removed it to watch people burn.. the same thing they must of been thinking adding target finders and shock charges