One of the issues that many people have faced when moving to Team System was how to integrate it with their existing project management software. Specifically, Microsoft Project Server.
Team System can already connect to Project professional, but project server is a much more robust solution for managing multiple projects and resources in parallel.
There was a sample Team System Connector for project server that worked with Beta 2 of team system, but the RTM version suffered for a long time until today I got the announcement that the VSTS Connector for Project Server 2003 is finally ready.
"The Connector synchronizes Project, Resource and Task data between the two systems. Project Managers, Resource Managers continue to work in the EPM environment while the development team works in the development environment, i.e. VSTS, and data seamlessly flows between the two systems. Updates to work items in VSTS are automatically applied to the corresponding assignments and tasks in Project Server and vice versa. Project Managers have complete control over the inflow of the actuals into the project plan. In addition, resource management functions for all development projects, like managing time and utilization for resources working across multiple projects, team staffing etc. can be performed in Project Server. Lastly, portfolio and program level reports can easily be generated for projects being executed in VSTS and managed in Project Server. "