One of my favourite additions to Visual Studio 2010 is the support for extensions.
Extensions are plug-ins that complement the featureset of Visual Studio 2010 and make the product (overall) much better through their addition. The reality is this: we can’t implement everything, but we have some amazing Partners and members of the developer community who can. By enabling this capability, we lower the bar of entry for these folks to extend the capabilities of Visual Studio 2010 so that the community (as a whole) can benefit.
He’s a quick screencast I recorded that highlights extensions and how they work:
If you’re interested in incorporating Visual Studio 2010 extensions then check out the Visual Studio Gallery!