Notcom has updated TinyUmbrella tool to version 4.30.00 and is available to download for both Windows and Mac OS X. iOS 4.3 support has been added to TinyUmbrella 4.30.00. Also, TinyUmbrella 4.30.00 supports all models of iPad 2. You could save iPad 2 SHSH blobs with TinyUmbrella 4.30.00 once it is released.
TinyUmbrella 4.30.00 also enables you to take backup of iOS 4.3 SHSH blobs. Not com has also mentioned that users should switch to this newer version as the earlier versions could make the SHSH saving job slower than in the future.
Download TinyUmbrella 4.30.00 for Windows and Mac from here