SeaWorld's official hotel partners are found here:
http://seaworldparks.com/en/seaworld-orlando/vacations/hotels/official-partners/
There's a nice selection of hotels depending on what you are looking for in accommodations, from the budget-friendly Springhill Suites to the more upscale Rennaissance to the larger villa-style rooms at Hilton Grand Vacations. Some properties have breakfast include, some will have free wi-fi and parking, others charge a resort fee but have more amenities (like the kids waterpark at Rennaissance).
We like staying at the SW official hotels for a SW visit (and did so before we purchased our timeshares), because the free Quick Queue for Seaworld is such a nice perk. You also get early entry on select dates, free access to the SeaWorld Rescue tour, and complimentary transportation to the parks.
We enjoyed the Residence Inn SeaWorld for our Christmas 2012 trip as it offered fully separate bedrooms, full kitchens, and lots of free inclusions like a hot buffet breakfast, parking, and internet. The pool area was nice and we loved the large courtyard with sport court. You can check out lots of pictures and our full write up in my trip report (click on the link in my signature).
For an Orlando vacation that included Universal and SeaWorld, I would definitely consider a split stay to take advantage of the onsite perks at each set of parks. Plus, your driving from place to place at the end of a busy park day is cut WAY down
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