iOrgsoft Studio has released iTunes to Kindle Fire converter for the Mac. The free app lets you convert/import/transfer iTunes movies/musics from your Mac to a Kindle Fire.
You can convert files in the MP4, MOV, M4V, M4A etc to MP4/H.264/MP3 formats. iTunes to Kindle Fire also offers editing functions such as trimming your movie clips, adjusting contrast, color and brightness, and the ability to splice your clips into a cohesive movie
iTunes to Kindle Fire requires Mac OS X 10.5 or above. For more info, or to download the tool, go to http://www.iorgsoft.com/convert-video/to-kindle-fire-converter-on-mac.html .