I haven't done it, but am considering something similar.
I was thinking of mounting our tv on one of the Thule Smart LCD TV Mounts
and it would be able to be moved to/from the outside and inside relatively easy. I'm just not sure if the mount will position the TV very well inside.
For the connection, I found this
plate on eBay. Thought it would be easy to go right through the wall near the inside tv.