micropaymentsFacebook is expanding its Facebook Credits payments system across the site in a move to boost revenues from games and virtual goods.

Facebook first introduced a limted trial of its Credits system in in May 2009 as a way for users to buy e-goods from the Facebook gift store and a small number of third-party apps, but is now rolling this out to more app developers.

Facebook takes a 30% commission in line with Apple’s App Store commission.

With the rise in social gaming the virtual gifts economy this is a major revenue opportunity for Facebook. As Apple have shown in their App Store, making payments easy and people are much more likely to spend on digital content.

In the background is the battle to be the web’s micropayment engine. Many products are competing to unlock this potential goldmine, from early attempts at online currencies like Beenz (now closed), to retailers like Amazon, to eBay-owned Paypal and social networks, but surely the web is just too big?

As social networks, and Facebook in particular, increase their share of web usage their chance of having the kind of reach to become an ‘easier’ solution grows, but they will still be one among many.