Tom,
Waldenwoods is about a mile from my home base, and my cousin has been a member there for a number of years. It is a private membership RV resort and has a number of different amenities, some open to the public (not camping). It's not what I would call a five star RV resort, but it's nice for being as close to to Metro Detroit as it is. It's been about 8 years since I've been in there, but I do remember that the sites were small and close together.
Years ago they over-sold the membership and it was difficult for members to use the facility for camping, but I don't know if that is still an issue today.
Like any private membership RV resort, many folks don't like them. One has to use them a lot to justify the $$$ investment. Some folks will buy into them and regret it a year later.
I have nothing against private membership RV resorts, as a matter of fact I have been a member of OAI for about 15 years and it works great for me (OAI has five resorts around Michigan).
Waldenwoods:
http://www.waldenwoods.com/
OAI:
http://www.outdooradventuresinc.com/
Bob