@nprofile1q... Some problem with my wifi some time ago: detect but not connect. For italian networks be sure your /etc/rc.conf has something similar to "country IT regdomain ETSI":

wlans_iwlwifi0="wlan0"
ifconfig_wlan0="WPA DHCP"
ifconfig_wlan0_ipv6="inet6 accept_rtadv"
create_args_wlan0="country IT regdomain ETSI"