They're conceptually related. Fishbowl does not reference the FDT.
The Microsoft Facebook SDK is a good starting point for how to build something like Fishbowl. We didn't use it because it was still in development while writing Fishbowl and there were some different priorities between the two projects. Both
were being developed quickly and it never reached a point where it made sense to converge the two. We were in contact with the team that was writing the developer toolkit v3; there are some designs that are shared between it and Fishbowl.
The Developer Toolkit is much more designed to be a .Net wrapper for Facebook with multiple layers of abstraction available to suit varying needs depending on the situation. The WPF samples that are included with the current version of the toolkit
are based on an older version of Fishbowl.
Contigo is very specifically a WPF friendly wrapper on top of Facebook's data, not their APIs. E.g. FQL queries aren't exposed; updates happen automatically and the source collections raise change notifications; photo albums are a property
exposed on a contact; for the most part the FKIDs are hidden from (or at least not necessary to use) the public object model. It's similar to the BindingHelpers part of the Developer Toolkit. The library in Fishbowl wasn't vetted or tested as a
platform outside of the application. The FDT had more people focused on it for longer and should be more feature rich and polished.
I hope that helps,