Jennifer, the treehouse villas were part of the conglomerate that included the Fairway Villas and others, part of an overall villa complex. I guess that, other than the trailers at Ft. Wilderness, these were the forerunners of the home away from home concept. Disney pitched them as part of the lodging for the Disney Institute. A lot of the old villa property has been demolished for SSR.
We stayed in one of the Treehouse Villas years ago. They were basically houses on stilts, with two bedrooms, as I recall. They weren't bad, but they're nowhere nearly as nice as what we have through DVC.
These buildings were the main reason that we bought in to DVC at the beginning. We were staying in the treehouse villas right next to where OKW was built. Dad and I would play golf on the course that now runs through OKW and SS. We witnessed the construction from beginning to end and could not help consider the purchase of DVC when we were spending $2000 per week to stay at WDW every year. It was the best investment we have ever made.
The buildings are two story and from the bedrooms you can look over the balcony and see in to the living room. At the time they were very different from the accomidations at the other resorts on property. The view to the outside was nice as all of these buildings were surrounded by trees and plants.
Some of my best memories of vacationing with my wife and Daughter (her first visit to WDW was spent at the treehouses in 1991) along with my mother and father (who are no longer with us and always wanted DVC to be something we would pass along to other generations).
As one of the CM on the boat from Riverside to DD noted, the land on which the Treehouses Villas are built on, can not be developed further although the structures that are existing can be maintained but no other structures can be built in that location. I am sure Disney will find a way to refurbish that area.