Visual Studio 2010 Team Explorer Everywhere is Microsoft’s Team Explorer client for Eclipse-based environments. Here is the official description:
Visual Studio Team Explorer Everywhere 2010 helps .NET and Java development teams collaborate across platforms. It provides the tools and plug-ins you need to access Visual Studio Team Foundation Server 2010 from within Eclipse-based environments, so everyone can work together to achieve business goals.
Up until yesterday, Team Explorer Everywhere was sold as a separate product. It is now available as a free download. Keep in mind that although Team Explorer Everywhere is now free, you will still need a Team Foundation Server CAL. See Visual Studio 2010 and MSDN Licensing for details.
There has also been some changes to how TFS Reporting and accessing TFS from within Microsoft System Center Operations Manager is licensed (i.e. now free).