NTeam is a GotDotNet project that aims to integrate, for small- to medium-teals, Open Source alternatives to the features of Microsoft's VSTS. In an EWeek article discussing it, Eric Sink of SourceGear, says that “It is inconceivable that a community project could produce a Team System clone, which is truly suitable for enterprise use during this decade."

Highly unlikely, yes. Inconceivable, not at all. The myth that Open Source cannot produce enterprise-quality software has been totally discredited by several projects. The only question is whether a corporate sponsor willing to pay a handful of major contributors is necessary. I tend to think such sponsorship is necessary. Anyone at Borland or JetBrains paying attention?