I have been seeing odd imagery issues since updating to 3.6. I have several imagery services and one no longer even displays. Another one is completely fine and the one I use the most keeps cutting off the top part of the map frame and not displaying the imagery. When I pan around, it will update the map imagery, but still doesn't diplay any imagery for that couple of inches from the top.
We tried this on a computer that didn't upgrade to 3.6 just now, and that computer displays everything perfectly.
So the only difference is my computer having been updated to 3.6...