I've got bases covered I believe for deploying Exchange 2013 to an environment that is currently a 2007/2013 co-existence, however, I am not quite sure yet on what exactly happens once Exchange 2013 is joined to the environment.
Would any mailbox users of Exchange 2007 or 2010 notice any changes or issues?
At some point I would want them to notice changes but only after having communicated to them about migrating to 2013, and I'd want to let them know about that ahead of time of course.
Only thing I can think of for now might be the OWA access. Any thing have to change with that so people don't start pointing to Exchange 2013 as soon as it's deployed?
My goal is to deploy a 2 node Exchange 2013, then when it's running and updated, then I can communicate to end-users about the new server and migrate them over.