Microsoft have posted updated versions of the HD Photo Plug-ins for Adobe Photoshop Software to the Microsoft Download Center. There are now versions for both Windows and Macintosh OS X.
There is an updated beta for Windows Vista and Windows XP, plus a new beta for both Intel and PPC Macs running OS X.
In addition to the direct links above, you can always find the various HD Photo downloads by going to the Microsoft Download Center at http://www.microsoft.com/downloads and searching for "HD Photo".
Source:→ MSDN Blogs