My first test with Flash Player 10 was to convert an AIR project to a browser only version. I choosed RichMP3 as it was the simplest one. I just replaced all File/FileStream instances to the new Filereference and it worked. Ah yeah sure I had to use the dirty hack to load the mp3 from the client (convert to swf > load bytes via loader). All pretty straight forward. Now you can cut the mp3 file see id3 tags and even change them including cover art. You can replace the cover art with a new image Jpeg,Png and save the edited file back to your harddisk. It`s really amazing that you can do this kind of stuff now without a server just on the client:-) The Mp3 reader should handle most of the mp3 files out there but i`ve not tested this a lot so use on your own risk 😉 and let me know if you have problems.
Update: I had some problems running this with the Flash Player Plugin for Internet Explorer. The save function of the FileReference did not work for me only under Firefox. Do you have such issues? It`s really hard to debug without the debugger 😉