I personally think this is a bit too much. I can imagine how slow the screen would update if the video support is being used! If you want video integration, use Netmeeting. That's what that program was designed to be used for. mIRC is a text based IRC client, and that's how I believe it should remain! I could easily live without this ever being implemented into mIRC, and I hope it never is.
I think many mIRC users are forgetting what mIRC is all about. mIRC was never intended as a voice/video client. It is intended as a text based IRC client. I don't understand why that's not good enough.
On a final note, I heard for a while that there is a dll out there that allows voice to be used over IRC. I don't know the name or where to locate it. Try looking on an mIRC scripting web site that carries dlls.