There is a sheet included with the Stacked DVD set that promotes some other 20th Century Fox DVD releases that says WKRP in Cincinnati and The Loop are coming soon! More details as they become available.

Blog story with a photo of the insert saying this:

http://www.sitcomsonline.com/blog/2006/12/fox-finally-releasing-wkrp-dvd-soon.html

Thanks for posting this. I bought the Stacked DVD weeks ago, and did not notice that on the insert. I'll be getting it for sure.