The file attachment control doesn't seem to work with SharePoint/InfoPath in web browser mode. I get the error code base64binary is not supported.
One thing I thought of was a picture library. People attach photos to the IP form by clicking in the rich text box and pasting the URL of the pic in the SP pic library. It is a little cumbersome for users to do this though. If I don't find a better solution, I may have to publish to a shared location rather than a SP site as a web form.
Surely there must be some other way?