@notcom, the developer behind the tool TinyUmbrella has recently upgraded it to support the iOS 5 beta 2. Developers, if care then save their SHSH Blobs now. Even if Apple release iOS 5 beta 3 in future, you will be able to downgrade to iOS 5 beta 2 without facing any kind of error in the iTunes. Those who don’t know, TinyUmbrella also helps you to preserve the BaseBand of your iPhone 4 using TSS server, thereby, making your device vulnerable to ultrasn0w again.
If you are not a developer, we request you not to download the iOS 5 Beta 2 and upgrade the firmware. It will request you to enter your registered UDID after the restore process where you could stuck. It is assumed that Apple may release iOS 4.3.4 anytime in future. So, people looking for the iPad 2 JailBreak should save the SHSH Blobs too because Comex is on the verge of completing the his work. Also, don’t pirate the developer firmware to avoid any kind of issues in the future.
Check out for more info on SHSH Blobs here