You say:
This decision is not one we took lightly and was informed by customer feedback.
I have a hard time with that statement. I, as a cutomer, am providing you feedback that it was the incorrect decision. We are in the middle of a server rollout and want to use the most up to date Windows Server. We also want to use your most up to date Exchange Server. We can't. Plain and simple.
All the wonderful new features that 2008R2 supports and we can't take advantage of it because you decided it wasn't a good idea.
As a customer, our feedback is you need to fix this situation. I see a lot of other people in the comments above that feel the same way. Please stop with the forced Exchange 2010 upgrade. Perhaps that is not your intent, but that is how it feels.