In Marvel vs. Capcom 3: Fate of Two Worlds for the PS3 and Xbox 360, there are several characters you can unlock with the PP (player points) you earn during matches. Here is the list of characters I’ve found so far, and how much PP you need to unlock them.
Akuma – 2000 PP
Hsien-Ko – 6000 PP
Jill Valentine – Special Edition, or purchasable DLC available 3/15/2011
Sentinel – 4000 PP
Shuma Gorath – Special Edition, or purchasable DLC available 3/15/2011
Taskmaster – 8000 PP