I'm a web designer/developer, writer and animator living in Birmingham Ala. I have been working in the web design/development field for 15 years. I am a founding member of the writing and animation team 5 Guys in a Garage who started JabTV.com. I have worked for various internet and media companies over the years including the now defunct Hecklers.com and al.com.
So 7.4.1 erased the .m4r rename hack. So the super remarkable extra special re-hack is *insert drumroll* rename the file back to .m4a
Here is the link to the engadget article
