Chris -
LOL thanks for your posting! I did get this reply from support also on the 2nd:
In the scenario you described, the answer for GRT items is yes, but for an entire database, no. So you can restore emails, etc, individually to Exchange 2013 that were taken successfully with GRT in Exchange 2010. But restoring an entire Exchange 2010 database to Exchange 2013 won't work.
Just fyi, I also saw your forum post out there, and to answer the compatibility questions that I saw, 7.6.1.1 was released today, and it supports Exchange 2013 with CU7. It is on parity with 7.6.0.4. 7.6.1 was not; it was 7.6.0.3.
I guess I'll see sometime next week...! ;-)