Frequent readers of my blog know full well that we take TFS dogfooding very seriously here.  In fact, just this month we're celebrating 3 years of using TFS within the Team System team...pretty amazing.  As you might expect, usage is taking off in other groups as well.  To learn more, I'd recommend reading Brian's recent article on internal adoption of TFS.  In it he writes:

Our internal adoption team produced an update on our status this week and I thought I'd share the results with you.    We're now up to 21 TFS instances in production, hosting a total of 734 projects about 5,600 users.  2 of those instances are running an Orcas Beta 2 build.  3 are running a very early build of Rosario.  and the other 16 are running TFS 2005.  We plan on upgrading the remaining TFS 2005 instances to Orcas (TFS 2008) in August.

Read on to learn more and see some cool graphs showing # of users over time.