Per the documentation, this module requires the client to be using Flash 9 or 10. While this covers the majority of users, there are users with older versions of flash. In my case, when I tried the module on an IE client with Flash 6, the upload icon would not appear and no other message was presented to the user.
Adobe provides a toolkit for detecting the client's flash version here:
This is a request to enhance the module to provide additional detection of flash and providing a cleaner message to the user if they don't have a version high enough to work with image_fupload.
Comments and thoughts?