The DV camera wouldn't have the drivers you'd need to run the iSight. You can, however, connect the DV camera to the Mac and use it instead of an iSight in iChat AV.
I meant connecting it directly to a DV-camcorder and use it as a bullet cam (helmet cam). I've read that the camera inside the iSight is a Sony cam often sold as a bullet cam with the difference that iSight uses a DV connection where a Sony bullet cam uses analogue rca cables.
Anyone with a iSight and a DV-camera who can confirm whether this is possible? It would be highly appriciated. Thank you!