The polar bear exhibit is definitely quite a bit larger than what is shown in this photo (there are many more shots in the gallery), but interestingly enough the next project at the zoo is a renovated and expanded habitat for the bears. North Carolina Zoo is a brilliant park with many enormous enclosures, and there are high expectations. I've heard from several people that the African Pavilion, which now contains zero animals and only tropical plants, was excellent but the zoo felt that it had become outdated and all of the creatures were phased out in recent years.
The zoo has 2 male polar bears and while the exhibit is actually a decent one I believe that at the moment it is in the process of being renovated. The North Carolina Zoo is of extremely high quality and practically every animal habitat there is top-notch.
By 2013 the exhibit will triple in size, making it surely one of the best polar bear habitats at any North American zoo. The two-years of construction begins this summer: