The initial responses were sort of positive, but it's been a while without any feedback.
I know my 50D can beep - with AF focus confirm. It is not loud but it might be good enough for audio syncing with on top of the camera audio recorder (like 100$ Zoom H1 - BTW I just got a cheap shock absorbing mount for it from video noob store, works well), in most situations (unless it is really noisy).
All this RAW video stuff for 50D is cool, but will not be very useful without a good audio syncing solution.