Brian Harry's latest post lays out the roadmap for Team Foundation Server.

When I think about the TFS roadmap, I think about 3 different categories of things:

Servicing – These are Hot fixes, Service Packs, etc that fix bugs and add new capabilities to versions that have already shipped (today, that means TFS 2005)

Out of Band releases – We call them Power Tools (used to be Power Toys).  These are add-on tools/utilities that enhance the value of already shipped products without actually modifying them directly.

Major releases – These are the big new releases.  The next one is called Visual Studio “Orcas”.  In parallel, we are also actively developing for the release after Orcas, which I’ll describe at a high level.

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Please check out his post for a more specifics.