Workflow foundation is currently at 4th version. The main coding syntax that is expected for any of the code activities are more from the VB code syntax. Hence, it is proven that Microsoft considers VB as primary language while doing any kind of Research.
Apart of this, there is one more fact that there is a recent toolkit released from Microsoft, just yesterday, ie., 28th Nov 2010. It is RTW for Windows Phone developer. This release enables Visual Basic developers to create Silverlight applications for Windows Phone 7 using the final version of the windows phone developer tools.
You can download the Windows Phone developer tools RTW from this link.