EMM is early morning magic, where you get SDMT, PP, and Pooh plus breakfast from 6:45 am-10 am, for $69 plus your ticket for the day. DAH is Disney After hours, where most of the MK was open for 3 hrs past closing for $150 no ticket required and you could go in at 7:00. They have extended EMM through early fall, it seems to have gone over fairly well. They did not extend DAH beyond the few dates they had in April and May. I did both in May, and while I loved them both I personally liked DAH better. It was more palatable at $75 for AP holders, though. DAH was amazing, like having the park to yourself. We would do it again in a heartbeat. We are doing EMM again in August.
ETA- I guess I didn't answer the original question LOL. I do think the MK events may have been feelers for what people would be willing to do for all of the new stuff coming out in the next few years or so. I would definitely do this for Star Wars and/or toy story land, and Pandora. I would have to think about Epcot and FEA, might not be enough for me (plus I have 2 boys, not girls). But I think plenty of people would do it, maybe they could include the met and greet and a meal, or something.