Camcorder.info reviews the Sony HC1 Audio options:
Audio is very limited with the Sony HDR-HC3, as there is no micophone input jack. This is the biggest downgrade, in our opinion, from the HC1, and narrowly limits the consumer base. The HC3 instead features an "Active Interface" Sony proprietary hot-shoe that only accepts a handful of Sony brand microphones, which can only be purchased through Sony's online store. Furthemore, the only options available are a high-fidelity stereo microphone for $99.99 and a shotgun mic for $69.99. If there was a mic-in port that accepted XLR or mini-stereo, users would have a world of audio recording options available to them. As it stands these two microphones aren’t going to satisfy the true audiophile, and it's disappointing that, at $1500, Sony won't allow users to make their own, informed purchases.David Tames explains why the HVR-A1U might be better than the HC3:
In addition, it won’t be possible to use video lights or flash accessories if shooting with an external mic, since all three accessory options connect to this one singular shoe.
This is reason enough to go with the HVR-A1U, the best of both worlds, I got it cause it's a consumer camcorder with built-in mic when you need it to be, or put on the accessory shoe and you have a standard hot shoe for a light and two XLR connectors for audio gear, and it comes with a little shotgun that's OK for the most part, but any serious user will upgrade to a better mic.I'm also looking forward to see what Canon is going to do with the GL/2.