Skullgirls is in for a bumpy spell at the end of the year as it switches publishers, being temporarily delisted from the Xbox Live Marketplace and PlayStation Store before returning as Skullgirls Encore. What exactly this means for its players, and any DLC they own, depends on where in the world they are.
See, Skullgirls publisher Autumn Games had signed up with Konami to land an Xbox Live Arcade release slot (because of the wonky way Microsoft handles these things). Then there's a long and horrible story involving Def Jam Rapstar and lawsuits and layoffs, which Skullgirls dev Lab Zero Games explains in a blog post announcing the change. Basically, Konami wanted Autumn to pay for testing on patches and all the crowdfunded DLC, which Autumn didn't fancy. So they split, and Konami moved to have the game pulled from consoles' digital store.
All of which means that come December 31, the game won't be on sale until new publisher MarvelousAQL relaunches it as Skullgirls Encore, which is expected to be in January 2014. It'll launch alongside the first DLC character, Squigly, who'll be free for the first three months. People who already own it will still be able to play until the relaunch, mind. What happens next gets tricky.
On PS3, it'll reappear on the PS Store as a separate game, free to everyone who owns the original. As it's treated as a brand new game, it won't carry over leaderboards, achievements, saves, or DLC. It's okay, though--all the character colour packs will be bundled up, and available free to everyone "for a limited time."
On Xbox 360, it'll relaunch and reappear on the store with a title update and mandatory compatibility pack DLC. Leaderboards, achievements and saves will all carry over. The colour DLC bundle will be free for a bit here too.
As for PC, hey, as Konami were never involved, everything's grand and it's already renamed.