Hi Mark,
We agreed with VISIFire on offering VISIFire as an OEM embedded capability so buying a license to the charting extension will include VISIFire. We are planning to add other chart providers under the same object model which will support alternative technologies such as Flash and images.
We are planning in the near future to partner with more potential technologies to provide integrated VWG extension which inherit from the markets leaders. We have found VISIFire to be the most comprehensive charting solution in Silverlight.
Cheers,
Guy