I agree.  The ability to use the in-game vox even when AHII is minimized would be very nice.  I played Everquest II for a while, and its in-game vox was usable even when that game was minimized, and that was extremely handy.
Also, as Stoney has stated, his wish regards an improvement to the in-game vox.  The capabilities, or existence, of ventrillo and teamspeak are irrelevant to the point of this thread.