A new blog post on the Orlando Sentinel's blog reveals that Hagrid's Hut is indeed under construction at The Wizarding World of Harry Potter theme park:

Building permits pulled by Universal for the much-anticipated, highly secretive Potter project show that the resort is indeed constructing Hagrid's Hut. The setting, according to the permits, is being built for Universal by the Nassal Co. of Orlando, which specializes in themed construction projects.

While the permits offer few details, it appears Hagrid's Hut will be mostly for display purposes. The documents suggest the interior of the building will be used for prop storage.

http://www.mugglenet.com/app/news/full_story/2176