The Yesterland theme park website has posted a "then and now" look at Universal's Islands of Adventure park in Florida...  On the subject of Marvel Super Hero Island, I thought this bit of information was interesting:

QUOTE: Of course, the various photos from Marvel Super Hero Island in this article don’t show that The Walt Disney Company acquired Marvel Entertainment in 2009 for $4 billion. That means that Universal is now paying a licensing fee to a company owned by its arch-competitor and promoting that competitor’s movies. Meanwhile, Walt Disney World cannot use most of the prominent Marvel characters, even though Disney owns the company. Universal owns the exclusive theme park rights “East of The Mississippi” for the Marvel characters it is now using, as well as for other heros and villains associated with those characters. The term of the contract between MCA Inc. [now NBCUniversal, a part of Comcast Corporation] and Marvel Entertainment Group [now Marvel Entertainment, LLC, a part of The Walt Disney Company] “shall continue for so long as a THE MARVEL UNIVERSE [now Marvel Super Hero Island] shall remain open.” To be considered “open,” it must be “operated and maintained in a first class manner consistent with the highest standards of the theme park industry.” In other words, Universal’s Islands of Adventure park can keep the rights forever. If you want to read all the legal language of the agreement, dated March 22, 1994, take a look at the Marvel Agreement Between MCA Inc. and Marvel Entertainment Group, as filed with the U.S. Securities and Exchange Commission..

[Source - Yesterland]

The "East of the Mississippi" clause is interesting, since there are now rumors floating around about a possible expansion to the Disneyland Anaheim Resort being "superhero-themed".   It has also been observed that the newly-opened TRANSFORMERS 3D ride at Universal Studios Hollywood appears to have a very similar building layout and ride equipment to that of the Spider-Man ride in Florida...

I went to Disney Wolrd in February with some of the family, and I had to search high and low to find the Marvel Encyclopedia and a trade of Avengers: Earth's Mightiest Heroes.

That was it. Anywhere.

Universal's Marvel "island" has tons of Marvel merchandise on sale.  So odd that part of those sales go right to their biggest competition.  Almost a matter of who's going to blink first.  Universal caves and lets go of the rights to stop promoting Disney's property.  Or Disney caves and pays Universal to get rid of the contractual thing so they can take advantage of that property in their own parks. 

I enjoyed the Marvel area when I went to Universal in 2001. My wife and I are planning to go to Disney World in a few years when our daughter is old enough to enjoy it and I'm hoping that within that period of time that Disney gets the rights back.