I'm hearing rumours of a second date for MSG... Dunno if there's any validity to them, but it was from before the shows were announced, and all the other places were correct. EDIT: Although, looking at the schedule, I doubt it. It would mean 5 shows in a row, and Maiden (and DT) are getting old.
Also, CrimsonE, don't forget Halford was on that tour too, as was Motorhead with Dio in 2003. I wouldn't be surprised if DT got more than an hour.