I agree, that section was just fantastic. So many little details in the window shops, the crooked chimneys, all the little signs, and of course the Forbidden Journey, the queue alone is wonderful, much less the ride.
Alas this is all counterbalanced by the tight quarters, teeming throngs, and understaffing (Hogs Head bar had ONE guy both pouring beer and running the register in the afternon last Sunday). Hopefully in a year or so this will calm down (who am I kidding? 3-4 years at the minimum).
I liked a lot of IOA. The entry area and the Lost Continent had great theming with lots of cool shops selling stuff for adults, not the endlessly repeated Disney trinkets you see everywhere at WDW. The jewelry was better (well, better mix between high end and costume quality), and the guy hammer forging coin medallions was cool. The Seuss area was well done, even though I am decades away from cracking a Seuss book. Not so hot on the Marvel or classic comic areas, but YMMV.
Definitely going to add US to future Orlando trips, thinking about heading down there in the early Spring and staying there for a quick commando weekend. I'd say WWHP was a HUGE boon for their park.