<p>Around here we have been working with a bunch of Visual Source Safe repositories for about 10 years or so. </p>

<p>Now I want to get rid of sourcesafe and move on to Team Foundation Server.</p>

<p>Do you have any tips or tricks for me before I embark on this migration? What are the things I have to be careful about? </p>

<p>I am sure this migration will mean that our working habits have to be modified in some way. Do you think that these changes could be a problem for the organization? Think about a group of about 20 .NET developers in a single site.</p>

I just googled, but
this walkthrough
seems like a good reference, and it mentions the tool VSSConverter which should help you make the migration as painless as possible.
I would like to recommend one thing though: Backup. Backup everything before you do this. Should anything go wrong it's better to be safe than sorry.
My links aren't showing up. This is the address:
http://msdn.microsoft.com/en-us/library/ms181247(VS.80).aspx