Ken let me ask why is it a pitty.  Flv is the same as swf without the player.   Windows media player and many others can play flv.  An flv file is slightly smaller then swf.  When I create swf files, the save is a flv.  If you only want us to view it on site, then it might be a problem, but if you let us download it, there should be no problem.  Besides I can understand the sites being leery.  Its easy to hide code in flash files.  How many times has windows told you that it stopped a flash movie because of unsafe operation.

This is just my opinion