I just recently updated my Ubuntu 12. 04 (LTS) and after I updated it, I lost all Wireless connections.
There are no available networks connect to and there is not even an option for Wireless in the network settings.
It seems as if the Driver is not even there.
When I type iwconfig, it shows eth0, eth1 and lo, but that is all.. There is no ath0 or wlan0.
When I type lspci, my wireless driver is Atheros.
If you need any more information, let me know and I will post it ASAP!