Yep, you read that right.  If you’ve been following the Office 365 wiki pages, you may have seen the wiki post quietly go live yesterday. MVP Ivan Sanders has already found it, installed it, and blogged on it. Podium!

We’re excited to get the power of 64-bit processing out to you for directory synchronization in Office 365.

The underlying sync engine as has also been upgraded to the latest version of Forefront Identity Manager (FIM) 2010. FIM is installed silently by the directory synchronization set up process.

You can run the 64-bit version on the 64 bit version of Windows Server 2008, or on Windows Server 2008, R2.

More details, including the upgrade path from the 32-bit version, can be found in the wiki post, Directory Synchronization tool 64-bit support.