This is an announcement that hopefully will serve more as a reminder than news to every iPad2/iPad3 jail breaker on this forum.
We are expecting iOS 6 to hit the streets this Wednesday, September 19. As of this writing, if you upgrade to iOS 6 - you WILL lose your jail break. Guaranteed.
(1) If you wish to remain jail broken, stay at your current iOS (for most, that's iOS 5.1.1). We'll have to practice patience and hope that "the powers that be" develop a jail break for iOS 6 soon. Watch this thread for updates on a jailbreak for iOS 6: Official IOS6 Jailbreak Status Thread
(2) Save your SHSH blobs for iOS 5.1.1 now. See this reminder from f4780y about that: IOS 5.1.1 - Final Call for Saved SHSH Blobs before IOS 6 is released!
(3) Start being careful of/with your jail break. Only load the tweaks that are known to work with your iOS (or iPad generation - or both). We no longer have the luxury of an easy restore. If a tweak "breaks" your iPad - your only option will be to restore to iOS 6. Then, you will have to join the ranks of those who are waiting for the jail break. So, just be careful in installing tweaks...
(4) Speaking from past experience - do not let that red update badge on your Settings icon drive you batty (). Stay fqr, far away from that Software Update area in your Settings app. The key is, a jail breaker should never use any that function or any of the Reset functions offered in the iPad Settings app. They will not work and if you try to use them, they will cause you to have to use iTunes to restore your iPad. This restore will be to iOS 6 and so you will lose the jail break. Best thing - don't even look into the Reset or Software Update categories.
(5) If you've decided that iOS 6 now is better than a jail broken iOS 5.x, when the new iOS is released, simply connect your iPad to iTunes, make a back up and then select Restore on the main Summary page. iTunes will do its magic and, when prompted, you will be able to "restore from backup." If you decide to re-jailbreak again, once (if?) a jail break is discovered for iOS 6, all the Cydia tweaks you've purchased will be available for you to re-download/install without paying for them again.
Bottom line: As of right now, once Apple closes the iOS 5.1.1 window (probably within 24 hours of the iOS 6 public release) - there is no going back, saved SHSH blobs or not. If you have to restore, for any reason, it will be to iOS 6.
Again, watch the official iOS 6 jailbreak thread (linked above) for any jailbreaking news and updates.