We today discovered that Apple published eleven new profiles for various iPhone-operators. These files are compatible with iOS 5.1 and are set for release on March 9. This could indicate that iOS 5.1 will be released around that date, is will be available for the following devices; iPhone 3GS, iPhone 4, iPhone 4S, iPod Touch 3G/4G, iPad, and iPad 2.
The profiles that have been found by us are intended for operators in Japan, France, Greece, Finland, and Sweden. By updating the profile on the iPhone, it will make sure that the network connection will work correctly after Apple releases iOS 5.1. The iOS updates are normally rolled out at the same time worldwide, so everyone should expect iOS 5.1 to become available next month.
However, the question remains if March 9 is also actually going to be the release date. We expect that Apple could release iOS 5.1 simultaneously with the announcement of the next-generation iPad, which will likely take place early next month. But these are all rumors and it is hard to give a more precise indication about the iOS 5.1 release date.
Jailbreakers should start preparing themselves by saving their SHSH blobs before updating to iOS 5.1; this can be done with either TinyUmbrella or iFaith. The developer of TinyUmbrella said that this is especially important for iPhone 4S and iPad 2 owners, if they want to make use of a jailbreak again.