Apple reverses its stance on iOS third-party developer tools; Unity games and Flash apps incoming
We probably won't ever know the real reason for Apple's change of heart, but it's likely a gambit to ensure the iPhone and iPad remain top-dogs, at least as far as cool apps and games are concerned.
In other news, Apple is also publishing its App Store Review Guidelines! I'd like to think that Apple has finally seen the merits of transparency, but this is almost certainly a reaction to the continuing growth of Android and other open platforms. Still, once the guidelines are public, developers will never again be mystified by an app's failure to make it into the App Store.
Update: the App Store Review Guidelines are now available.