Although last we heard iOS 4.3 was coming in March, Apple just made the beta 1 version of the software available through its developer portal. The new version became famous days ago, as it was rumored to include the WiFi hotspot feature for the GSM iPhone that we’ve already seen on the CDMA one announced by Verizon.
iOS 4.3 measures 682MB and this update is bound to have something more than bug fixes, security updates and WiFi hotspot features, so we’ll be back once we learn more.