IOS 5.1 Update Released

IOS 5.1 was released today, and installing the upgrade will take the baseband to 4.12.01 (iPhone 4) or 2.0.10  (iPhone 4S).  Neither baseband version is currently unlockable nor will they be anytime soon.

Downgrading to IOS 5.0.1 and thus downgrading the baseband is currently possible.  Just hit the "Shift" key while clicking "Restore" in iTunes and select the 5.0.1 firmware (ipsw) file.  By default, iTunes downloads firmware files to C:\users\X\AppData\Roaming\Apple Computer\iTunes\iPhone Software Updates

If the files are not there, they may be manually downloaded from www.limera1n.cc

As always, if you want to downgrade to IOS 4.X, you'll need an SHSH blob for your phone created with TinyUmbrella