We just spent a weekend at Great Wolf Lodge at the end of March and had a great time! No problems at all. (I hadn't heard that they had problems like that.) I have an 8 year old and a 3 year old, and my daughter took a friend. My 3 year old liked to hang out in the kiddie pool, and the girls did all the water slides. Besides the kiddie pool, they actually had a few small slides that my 3 year old could go on. GWL had something there for all ages and swimming abilities. I would go again, though probably not for an entire weekend.
I have heard that Kalahari is awesome for older children. They are in the process of expanding to make it twice its current size.