Being that I was so irritated with Team System dying on me, in addition to the relative immaturity of the interface there, I decided upon return from Tech Ed to change direction and move the team to SourceGear's Vault product. In addition to Eric Sink being a stand up guy and blogger community figure, the sourcegear vault product has frequently been a favorite of mine in the 3.* version days at other jobs.
So today we purchased the latest version of Vault and I'm pleased to say that the initial set up and administration was a breeze. Even though I had no experience in the 4.* versions, the new web interface was comprehensive and the little documentation I needed to use was more than sufficient to get me going. I wouldn't consider our source code needs on site to be overly complex (branching/merging/etc) so I can't comment on those features, but Vault offers a whole lot over standard source safe in a very easy interface.
One thing to point out, sometimes it's the little things that matter. When I was adding a folder to vault source control, it was smart enough to pre-select actual code files, ignore source safe files by default, and ignore my bin folder by default. It's actually kind of sad after my years of sourcesafe that such a small thing makes me happy. Shows how low Microsoft sets the bar on that product.