I haven't had a chance to look at VS2010. Is there a built-in Microsoft Grid for WPF or Silverlight yet?
A WPF grid is already available with the WPF Toolkit - October 2008 Release and will be included in VS 2010, or some version of it anyway.
There was a Silverlight Grid released back in October. There are some links and such to get it to show up in Expression Blend too. One has to assume it will also be included in the new IDEs as well.
Please keep in mind that the current Visual Studio 2010 release is a CTP (or Community Technology Preview). Many of the features aren’t there yet like the new WPF shell. In fact the only way to run it is through a VPC image. Just keep an eye out for the beta to get a better feel, but to answer your question, yes a Grid should be part of the core package. As others have pointed out, the WPF and Silverlight toolkits have versions today and you can get the source too.