Hi,
If you're prepared to go through the learning curve, and know how to deal with the downsides of
DSLR's, you can actually get awesome images out of these inexpensive cameras. I just finished a feature-length documentary shot almost exclusively with a 7D and 60D.
If you're going to be working primarily with one microphone, then the Magic Lantern Firmware 'hack' will
allow you plug your mic DIRECTLY into your 60D or 5D [among others... not 7D, alas] - and you can MONITOR your audio, too!
http://vimeo.com/20978887
I've been using this feature a lot lately it's working out great for me.
For more than one mic, yes, best to use a Zoom H4N or Tascam to record your audio.
Wayne
