We built a similar app for internal use, with the addition of real-time collaboration (flash-based audio/video chat + NetMeeting-style abilities to draw, type,

We built a similar app for internal use, with the addition of real-time collaboration (flash-based audio/video chat + NetMeeting-style abilities to draw, type, etc. on the reviewed document). While this requires a central server to stream a/v and good connection, it's quite popular around here now.