I tried your code on a WinXP 64-bit workstation connected to SQL Server 2008 64-bit. I always get this error:

Cannot bulk load. The file "C:\TestBook.xml" does not exist. at line 1

Msg 50000, Level 16, State 1, Procedure uspImportExcelSheet, Line 497

Cannot bulk load. The file "C:\TestBook.xml" does not exist.

No matter where I put the "TestBook.xml" file ("C:" or a network drive), it cannot find the file.

Am I missing something?