ODBC 3.8 is in beta 1 of the Windows 7 SDK...
And beta 1 of the Windows 7 SDK is now available on http://www.microsoft.com/downloads/details.aspx?FamilyID=a91dc12a-fc94-4027-b67e-46bab7c5226c&DisplayLang=en
ODBC 3.8 includes new features such as
· Executing connection operations asynchronously.
· Streamed output parameters.
· ODBC C data type extensibility.