I used to love Tribes2 so this could be very interesting:
http://www.shacknews.com/article/69078/tribes-ascend-free-to-play
http://www.shacknews.com/article/69078/tribes-ascend-free-to-play
Tribes: Ascend is being billed as "the multiplayer successor to the much lauded Tribes 2." Built on Unreal Engine 3, Ascend will be a downloadable multiplayer shooter for PC and Xbox 360. And, surprisingly, it will also be free-to-play.
Yes, like Team Fortress 2 and many MMOs, the game will be entirely powered by microtransactions. According to a report by IGN, Ascend is largely inspired by League of Legends' cycling release of warriors. In Riot's game, new "champions" are made available for purchase every two weeks, for about $5-10. Tribes: Ascend will, instead, allow players to buy entire loadouts. One loadout may give players more engineer-type attributes, while another may focus more on stealth. Developer Hi-Rez is hoping to create new loadouts on a regular basis, in addition to making cosmetic enhancements available for purchase as well.
Given the competitive nature of online multiplayer, Hi-Rez faces an uphill battle with making Tribes: Ascend a free-to-play game. In spite of the purchasable loadouts, gamers need to be assured that matches will always be balanced. On the other hand, Hi-Rez must constantly come up with new ways of ensuring gamers are incentivize to buy more. It's an interesting experiment, and definitely a sign of things to come.