08-17-2009 12:44 PM
There actually aren't any new APIs in 5.1.1. For a list of changes between the major AMT releases you can look at the Network Interface Guide (for SOAP API changes/additions) and for the WSMan Interface you can look for changes documented in the Intel AMT WS-Management Capabilities Comparison.
Another useful document in the SDK is the Versions.txt file.
I am pretty sure that the only change going from the SDK 5.1 to the SDK 5.1.1 was a fix to the Redirection Library. I'll let you know if I find out otherwise.