As I was at the open house that our local Jayco dealer had this last weekend I was checking out all the 2016 models and noticed that most if not all trailers are now wired for a solar hookup and have a plug on the A frame.
2015 models were also, at least the Jayco Eagle 27.5. My buddy is here camping at my house for hunting season and that is the first thing I noticed on his 5th wheeler.