I've read a few reviews of it from runners on other message boards, and they all have good things to say.
I've toyed with the idea of doing the Goofy Challenge in WDW sometime. You do both the WDW half marathon and the WDW Marathon on the same weekend. I think most people's strategy is to run/walk the half so their legs aren't toast. It's held in January every year, and it's already sold out for 2009.
http://disneyworldsports.disney.go.c...RaceDetailPage