As we enter the year 2010, the status of developer tools from Microsoft is a bit confusing. Visual Studio 2008 is released while Visual Studio 2010 is at beta 2. Silverlight 3 is the released version while Silverlight 4 is at the beta stage (but only for VS 2010). MVC version 1 is released while MVC 2 is at RC the stage (but only on VS 2008). WCF RIA Services is in beta on VS 2008 but is still a preview for VS2010 (part of the Silverlight 4 package). [Note: I think I have that all correct.]
Since I like to provide videos on the latest and (hopefully) greatest stuff, I am kind of stymied by the different bits that vary across VS 2008 and VS 2010. This will all likely synch up come around April or May of this year, but until then, things are tough.
What I plan to do in the meantime is try to figure out all the new stuff and write a couple of tutorials using what bits I can make work. Right now I am working on a VS 2010-based Silverlight 3 project that uses ADO.NET Data Services. Most of what I will include will work with VS 2008 and will likely work without any changes when VS 2010 is released.
Having "off-cycle" products is nice, but at times like these, it makes for whole lot of confusion.