Killer Instinct got a huge patch today and added some new goodies along with some bug and balance fixes.
The first big thing about the patch is that Sabrewulf is now the free character you can play in the game instead of Jago. Jago is still the character you play in Dojo mode so you pretty much get to try out two characters for free instead of one. You just cant use Jago in single player or multiplayer matches until you buy him.
The other big thing that comes with the patch are the classic costumes, complete with accessories for Orchid and Jago. I have the Ultra Pack, which will give you the costumes free so i'm not sure if they are available to buy in the store yet, but if you have the Ultra Pack, you are good to go.
As for the bug fixes, locked costumes can now be bought in the store after reaching the requirements. I can now finally buy Sadira's 5th color. I've waited so long! They also changed how much XP you win or lose in online fights. One big complaint was that you could lose almost an entire rank from losing a single match online.
You can check out the full list of patch notes on their official forums.