When the first beta of iOS 6 was released, it became readily apparent that the three year-old iPhone 3GS was not going to be capable of handling many of the GPU-intensive improvements to the software. These included Maps Flyover and turn-by-turn navigation, as well as the less intensive shared Photo Streams and VIP Email folders.
In the latest beta released yesterday, users discovered that the latter two features — shared Photo Streams and VIP Email — were added to the 3GS and references to their absences removed from Apple’s developer support page. Looks like Apple made some magic happen behind the scenes and found some way to make them compatible.
There are still millions of happy 3GS users out there, and they’ll be updating to iOS 6 on the same day as everyone else.
Source: Apple Insider