I've just installed the RC1 and am hoping to play with it now. In the install notes i saw this:
"ShapeFileFeatureSource.ExecuteQuery function isn’t supported for 64 bit system, because the Microsoft.Jet.OLEDB 4.0 isn’t supported on a 64 bit system."
Apparently M$ released one on April 4th.
I was looking for a 64bit OLEDB provider the other day for some custom shape file reading and stumbled upon this:
64-Bit OLEDB Provider for ODBC (MSDASQL)
microsoft.com/downloads/details.aspx?FamilyID=000364db-5e8b-44a8-b9be-ca44d18b059b&displaylang=en
Overview
The Microsoft OLE DB Provider for ODBC (MSDASQL) is a technology that allows applications that are built on OLEDB and ADO (which uses OLEDB internally) to access data sources through an ODBC driver. MSDASQL is an OLEDB provider that connects to ODBC, instead of a database. MSDASQL ships with the Windows operating system, and Windows Server 2008 & Windows Vista SP1 are the first Windows releases to include a 64-bit version of the technology.
Supported Operating Systems: Windows Server 2003 Itanium-based editions; Windows Server 2003 x64 editions
This update is only supported on Windows 2003 SP1 and Windows 2003 SP2 64-Bit OS
I haven't tried this yet, but thought i'd share it anyhow. May be worth a look.