Silverlight - very very very slow

I've read several places, both blogs and forums that people are so impressed by the speed of Silverlight..
I must regretably say that I'm not one of them. I hope this is just the case with the Alpha version of Silverlight 1.1 and that the performance will increase when it reaches release.

I applied texturemapping to my 3D engine yesterday and the FPS (Frames Per Second) went from about 30 FPS to 2-3 FPS. I can easily switch back and forth and see the difference clearly. The test object I have have about 400 faces visible at every given time, and the area they are filling is not big. As I mentioned, I hope this is just the case with the early Alpha release, or even better, I hope it is a problem in my code.

I will be investigating this further and post my findings.