It looks like for 200 points you can purchase the Winter Warrio Pack which adds festive costumes for Kameo and her transformations.
The Winter Warrior Pack is now available at Xbox Live® Market Place, and adds some fun, new holiday and winter-themed costumes to Kameo and the Elemental Warriors!
1up.com is not too impressed that the costumes will set you back basically $2.50 USD to get costumes.
Of course, that basically means you’re paying $2.50 in order to unlock a set of costume. Unlockable, alternate costumes and holiday themes have traditionally been bonuses created by developers as a treat for players (Sonic Adventure, Animal Crossing?), not microtransactions they have to shell out their credit card for.