Last Friday I passed the 70-669 TS: Windows Server 2008 R2, Desktop Virtualization exam with a score of 943. I don't know why it took me so long to get around to this one, but with this exam I now hold the MCITP: Windows Server 2008 R2, Virtualization Administrator credential.
I add this to my other MCITP certifications - MCITP: Enterprise Administrator, MCITP: Enterprise Messaging Administrator, and MCITP: Enterprise Messaging Administrator 2010. All this makes for a very busy looking business card, but it's worth the hard work!
I didn't do much studying for this exam. I've done a number of POCs and demos of App-V, Med-V and Windows 7 XP mode, so I wan't expecting much difficulty. It helps to have written the Hyper-V Unleashed book, too. :)