We hit Universal Studios and IOA last summer. I loved IOA as it had some of the best water rides I've ever been on....completely drenched, Dueling Dragons (fire dragon) rates real high in my book, Hulk was ok but anticlimatic (nice takeoff but felt like someone needed to get out and push afterwards), spider man ride was good, I loved the fast pass system...heck I'll pay 15 extra bucks any day to be able to walk past a 60 minute line on all the good rides, and their anual pass is significantly cheaper than disney.
I didn't care much for US it's self except MIB, and back to the future. All those jaws, twister, etc...were completely boring.
My main grip with Universal is their desire to barbecue you. I had my 7yo on the outside left of the Jaws boat and the explosion terrified him. I had to put him on the other side of me real quick to shield him from the heat. It was so hot that it was painful to me so I imagine how he felt. Twister wasn't much better as the fire there was very hot too, luckily I ducked behind some other poor unprepared soul.
Of course this year I'm getting my son and I anual passes to WDW, not decided on the anual pass for IOA/US yet but the new ride at UA looks good...however I did read that they are going to try to barbecue people in it....Goverment regulations made them turn down the heat in one part of it because (and I quote) "you could litterally warm your sandwich in there, regulations said that the heat can't be over 120 degres (that may be off don't remember) on a persons forehead for x number of seconds."
Just have to remember to take 2 fire retardant hat's/ponchos to ride it......