Boy Genius Report suggests that Apple will be releasing iOS 4.3 beta 3 today to developers. According to their sources, the release will be build number 8F5166b and, as BGR mentions, will be the third release in so many weeks if it appears today. Apple must be keen to get this update out the door.
Beta 2 was released on January 19 and is rumored to have a PhotoStream service, iPad FaceTime support, PhotoBooth apps for iOS. Here's hoping Apple's rapid development gets this OS into out hot little hands soon.