If you have noticed today when you open Cydia, it now shows your SHSH blob for iOS 4.2.1. I think it is due to the RedSn0w 0.9.7, the recent untethered jailbreak tool for iOS 4.2.1 devices i.e iPhone 4, iPod 4G and iPad.
Save Your iOS 4.2.1 SHSH Blobs
