Other phrases with a similar meaning:
"I'd Tap Dat"
"She Is HOT"
You get the idea....but for those of you that don't...refer to example.
...You are walking down the road with your mates...a good looking girl is walking towards you...the person that sees her first says 'Wa-Boov' while punching the air with your fists...your other friends should join the 'Wa Boov'ing if they are in agreement.