In the latest iOS 5.1 security page, Apple specifically credits jailbreak developers for finding potential security holes. Apple started reporting on the specific security holes they were patching when iOS 5.0.1 rolled as an over-the-air update. Apple is crediting pod2g
and the 2012 iOS Jailbreak Dream Team. Pod2g is credited for two exploits, while the 2012 iOS Jailbreak Dream Team is credited for one. This is the first time Apple has publicly credited members of the jailbreak community for discovering security exploits.
[Security Content of iOS 5.1]