This post on the Ubisoft forums offers details on the upcoming Rainbow Six Vegas 2 "Fan Pack," a collection of new content for the tactical shooter sequel. The Fan Pack will be released for the PC, Xbox 360, and PlayStation 3 some time next month, and the post offers full details on the pack, which includes new ranks, new A.C.E.S., a grenade indicator, balance tweaks, gameplay changes, and three new maps. There's also a trailer showing off the pack on the front page of the Six Vegas 2 Website. Here's a bit that mentions the new maps and clarifies that this is called a "fan pack" for a good reason:

There are three maps included in the free DLC: Murdertown – Dark, CQB Training – Dark and best of all the much-requested fan favourite Calypso Casino! The three map layouts have not been changed. The re-lit “Dark maps” have a very eerie atmosphere, and may require players to use night vision to spot enemies. Calypso Casino returns with updated lighting and textures. The three maps are playable in all Versus modes and Terrorist Hunt.

This Fan Pack is dedicated to all of you in the Rainbow Six community. Everything in this update and DLC comes directly from you on the forums, private messages to us and even matches the team has played with you all online. We’d like to sincerely thank you for your continued support and feedback. See you online!