TF2 is the Kickasso of games as a service
Seattle game maker, Valve Software has released updates for all 9 player-types in my favorite cartoon shoot-em up, Team Fortress 2. At $20 for the initial purchase and no recurring fees, Valve has kept the TF2 fan-base growing over the past two years by releasing free updates. New weapons and abilities that keep the game balanced, while making it more fun for more people. Oh, and free comic books.

Detail from 'Loose Cannon,' a free web comic released by Valve as part of their Engineer update, the 9th player class to be updated over a 2 year period of free releases by valve Software.
Valve makes their money through new players, not current player subscriptions. As a result, the current players spread the word for free. Go figure.
Other game franchises might have released these updates as a new product, called it TF3, and charged another $59.99. Valve has had a number of hit games, including Left 4 Dead, the highly acclaimed Half-Life series, and Counter-Strike: One of the biggest selling multi-player games ever. So maybe they don’t need to charge for updates.
I happen to be an enthusiastic TF2 player. The game has been the best $20 I’ve ever spent.
More about TF2 as a service from the Develop 2010 conference. (via Shack News.) http://www.shacknews.com/onearticle.x/64739
Valve Software: http://www.valvesoftware.com
The Engineer Comic http://www.teamfortress.com/loosecanon/
