We got off the Wish on Friday 9/16, drove straight to Miami and were in the cruise terminal before they had even called boarding group 1 (we were boarding group 3). I'd say we made it onboard the Dream around 4 hours after getting off the Wish.
Overall we enjoyed the Wish and wouldn't hesitate to book the Wish again (though there were a few things we really were not fans of). We're Platinum and I'd say that we were a actually a little relieved to be back on one of the older ships. The familiarity was comforting. We knew exactly where to find things and had a good feel for what time we needed to show up for things. Both were pretty full, but there seemed to be a bit more chaos around the Wish. The passengers were trying to get their bearings, and most of the crew seemed to be pretty high strung.
It was cool to be able to experience the Dream with the Wish so fresh in our minds, and we were ticking things off "Better on the Wish" here, "Better on the Dream" there. But we never felt like the Dream was especially worn out compared to the Wish. Oh, except the couch in our stateroom. That sucker would make a 1972 pinto with 3 bald tires and one brown door seem shiny and new by comparison.
We decided that we'd probably wait for the "inaugural" premium to fade before booking the Wish again, but I don't think we will feel like we're really missing out by booking a Dream Class ship (or even a Magic Class) over a Triton Class.