This download allows you to export and save to the PDF and XPS formats in eight 2007 Microsoft Office programs. It also allows you to send as e-mail attachment in the PDF and XPS formats in a subset of these programs. Specific features vary by program.
This Microsoft Save as PDF or XPS Add-in for 2007 Microsoft Office programs supplements and is subject to the license terms for the Microsoft 2007 Office system beta software. You may not use this supplement if you do not have a license for the software.
Amarjeet Rai's Blog 
Won’t work on XP x64
Yeah, I’m afraid your right.
That’s Microsoft for you. And why x64 is not a good move, yet.
Oh! Thank for nice post about Microsoft Office 2007 Add-in: Microsoft Save as PDF or XPS. If you want share more about this topic, you can read it at http://forum.techwoo.com/#715_microsoft_office__addin_microsoft_save_as_pdf_or_xps