MSDN Forums item on deployment:

http://social.msdn.microsoft.com/Forums/en-US/vsto/thread/cc1491b8-52a5-4a38-bd15-45dd9120018b/

and another:

http://social.msdn.microsoft.com/forums/en-US/vsto/thread/887d1f9d-7e7e-4042-999e-baccd31d32ab/

and another (more detailed):

http://social.msdn.microsoft.com/Forums/en-US/vsto/thread/1666d2b0-a4d0-41e8-ad86-5eab3542de1e

and with regard to ClickOnce:

http://blogs.msdn.com/vsto/archive/2008/05/08/adding-the-office-primary-interop-assemblies-as-a-prerequisite-in-your-clickonce-installer-mary-lee.aspx

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