Article:

A Custom Action for Deploying Visual Studio 2005 Add-in:
Having developed a Visual Studio 2005 add-in recently, I found that when it comes to deploying the add-in, there is no setup project automatically created any more. As described in the following excerpt from MSDN online, Visual Studio 2005 now relies on the .addin file for add-in deployment.

http://thecodeproject.com/useritems/AddinCustomAction.asp