There is a new method on how to crack WPA/WPA2, and that's WPS cracking
Backtrack5 R2 already has required tools installed, their names are "wash" and "reaver".
with wash tool you scan all the routers that have WPS enabled.
and with reaver tool you crack the PIN of the WPS enabled router.
It's about brute forcing router's PIN and takes about 10 hours to complete