OpenFeint, the mobile-social gaming network recently acquired by Japan’s GREE for $104 million, is adding a bottom-scrolling news feed to apps in its network. The idea is to provide a way for players to see what their friends are up to in other games, and provide new viral channels to developers to help get their apps discovered.

The company boasts that it reaches 90 million registered users, almost twice as many players as Apple’s Game Center — which also received some minor updates after Apple’s developer conference keynote yesterday in San Francisco.

Named GameFeed, the stream is supposed to be a Facebook-like feed for mobile games. Gamers playing integrated apps will see a stream of updates scrolling by on the bottom of their screen, which will show off achievements won by friends and friend suggestions.

Developers can choose to integrate it into their apps through a line of code. Yes, it takes up precious real estate on very tiny mobile screens. But it also provides more visibility to the network and the games promoted within it.