Citibank is granting certain cardholders the ability to pool and promote their reward points through Facebook, marking a pretty cool advancement in banks’ P2P attempts at playing a part in defining social currency, and one we’re sure its customers will enjoy.

Today, Citi launched a Facebook app that allows its ThankYou Rewards members who are Facebook friends to pool their points together to purchase everything from a weekend getaway to making a donation to a charity. To join the new program, cardholders must link the ThankYou Point Sharing App to their personal Facebook page. Citi says it doesn’t share account information through Facebook.

Though Citi says it’s the first bank to debut such a loyalty program, alternative payments providers have been attempting to innovate the social currency space as well. PayPal, for example, allows users to make payments through Facebook. Plus, we imagine that Citi’s annoucement is just the beginning of big banks using Facebook’s real estate for rolling out some of their financial services simply because that’s where their customers are.