With the new iPad 3 and Apple TV 3, it's been quite busy. Add to that all the cool new information surrounding a few new iOS 5.1 jailbreaks and we have quite the party.
TinyUmbrella now has support for saving 5.1 SHSH for Apple TV 3 and the iPad 3 (all versions). As of now we still cannot restore them but we are working on getting that working from a bunch of angles. I'll let you know more when I do.