If we get a great coder, it may be possible to start it up, have a FH2 tutorial to help set it up, and ofcourse code it to work - then yes, it would be awesome and totally transport gameplay.
But you can't do anything with the fact that, generally, only 2 or 3 people in any squad use VOIP at all, although more may have mics on.
And only like 2 squads in a faction of 5 - 7 squads will use VOIP at all.
So y'know - we need to look at the culture. If it is setup to start up and ppl have it active, even not speaking, you will still hear ppl around you.
Alternatively, beef up the commo-rose + optional VOIP, and you're good to go - And its more truer to FH2 philosophy.