Regardless of whether you have installed Silverlight for VS 2008 or VS2010, you will want to install the additional Silverlight Toolkit:
This toolkit gives you additional controls, components and utilities released outside the regular Silverlight release cycle. This is good news because Microsoft is releasing new Silverlight functionality iteratively. Rather than providing these controls with a “big bang” release, Microsoft is releasing them iteratively to get feedback from the developer community (can anyone say “user stories”) before officially including them in the product.
These new controls are designated with different quality bands, indicating their level of maturity. This helps you decide whether you want to include them in your projects right now, or possibly wait until more mature versions of the controls are released. Here is a list of the four quality bands, listed in ascending order from least to most mature:
Check out this link for a description of each quality level: http://silverlight.codeplex.com/wikipage?title=Quality%20Bands&referringTitle=Home.
This kind of iterative release is a good example for developers to follow. Software developers often have difficulty “letting go” of their code because they don’t want to put something in front of end uers that isn’t perfect, so they wait until they are finished to get feedback. The problem with this approach is that users can’t really provide solid feedback until they have something in front of them that they can play with. So, developers who wait until their software is complete before letting users provide feedback often find themselves rewriting and refactoring their code, and ultimately delaying the release of their software.
The moral is, get feedback as early and often as possible!
Chieft Architect, MM .NET Application Framework