Out of my league! I can only parrot things I've heard about AC benefits elsewhere, and they've mostly already been mentioned here.
AC advantages:
1) can be more efficient;
2) easier to implement regen;
3) seem to be higher RPM capable, so a 1 speed gearbox can save some weight/reduce drivetrain losses;
4) cool Jetsons sound!
Aside from all the AC drive hybrids, I've driven one OEM AC EV (Solectria Force sedan), and I liked it a lot.