Thanks for looking into it though...I'm not sure where else to take it, I mean I can and have re-installed silverlight, and I mean it works AFTER I go back, then back into upload so silverlight is working fine. I also know the upload on the silverlight demo site works fine.
I also did disable every FF addon, and it still happened
Are you trying it on a IIS deployed site or the VS localhost Casini webserver?
Here's another video showing more detailed firebug script debugging (with fiddler watching)
Notice the clear script error without checking the counts or null and trying to use the object.
I have no idea why it's undefined on my firefox instances, but it is....