I just posted the following note on the codeplex homepage to clarify.
Source code and downloads for Cocktail 2010 v1.x
The Cocktail development efforts moving forward will be focused on Cocktail 2012 v2.x. We continue to support Cocktail 2010, but discontinued the downloadable zip file containing the binaries, source and documentation. The binaries are now exclusively distributed through NuGet. The source code and documentation can be downloaded from Github.
Edited by mgood - 29-Nov-2012 at 11:50am