For us, there are three factors. 1. the Pool (that could also be factors 2 and 3 as well, we like it SO much); 2. location - we catch the boat to MGM, walk into EPCOT, walk through EPCOT to catch the monorail to MK (this most recent trip, the only time we got on a bus was for either a REALLY early morning at MK, or REALLY late evening at MK); 3. the bright airy feeling of the resort.
Now, a downside, for us, is breakfast... we don't like the little setup they have, just off the lobby, don't want to walk over to the Boardwalk Bakery, and don't always want to sit down for Breakfast. This is part of the reason we're trying out AKL in April. I really like having Mara downstairs to grab a quick bite, and of course, LOVE the idea of the animals. I'm kind of wary of the fact that AKL seemed kind of dark (at least in the lobby)... but I'm hoping we'll get over it.