More avatar costumes are in bound from Capcom in the form of Super Street Fighter IV packs for the digital people living on Xbox Live.
The packs will let you dress up your Xbox 360 avatars with "cool" Super Street Fighter IV items. No price has yet been mentioned.
Capcom says that 16 characters will be available starting with Ryu, Chun-Li, Guile and Ibuki. I don't, unfortunately, see any Blanka masks.