Eric,
I was under the impression from this post:
http://cutesoft.net/forums/thread/53844.aspx that an UploaderProvider would remove the need to store/write anything to the file system. In fact the UploaderProvider property SupportFS and method appear to indicate such (ie. if SupportFS is false and GetFSPath throws a NotSupportedException what purpose do these serve?).
Thanks,
Rob