Many recent reports have revealed that iOS 5.1 may be released on 9 March 2012. The most recent update about ios 5.1 was that Apple has published new profiles for many phone carriers which are compatible with iOS 5.1 and are set for release on March 9. So it seems obvious that the 5.1 version will be available soon for iPhone 3GS, iPhone 4, iPhone 4S, iPod Touch 3G/4G, iPad and iPad 2.
The released carrier profiles are intended for operators in Japan, France, Greece, Finland and Sweden. These updated include updates to the default APN, special dialing codes and other items that will ensure smooth network connectivity after an ios 5.1 update is downloaded.
Due to shortage of ipad2 in the market it is expected that Apple is going to release iPad 3 and most probably the release of ios 5.1 and ipad 3 will be on same dates.
As I reported earlier ios 5.1 beta versions are already released for developers and I believe the hackers are also working to jailbreak ios 5.1 and after release of ios 5.1 we will start struggling to jailbreak it with the help of our loving hackers/jailbreakers.
Note: If you intend to upgrade to ios 5.1 I recommend you to preserve the SHSH blobs in case you may need to downgrade if unlock is not available for new iOS 5.1.