I know I'm going against the grain, but as I've said before, I don't really have any solid reason to truly "complain". Sure, it stinks...and it really is bad timing for us. We've done at least 6 or 7 prior trips in July and never even looked or cared what time they closed because our kids were really too young to stay out really late (we're not late night owls ourselves). So we never stayed past 10pm anyway. Now, they're 13, 9, 9 and would be capable of an 11pm closing...and of course this year they're going to close at 10pm. But I really can't complain about it. The park is still open 13 hours (it's 9am opening, right?) during the day, hard to complain about that.
With the 10pm close, we'll have the opportunity to close the park several times, and that's great. So while we're disappointed, really it's not that big of a deal. I have no idea why they're doing it, but my guess is still that the staffing they would have devoted to keeping MK open late is now being used to keep AK open late. Keeping both MK and AK open to 11pm or later every night would have been a much bigger expense and strain on their resources.