Comment 5 for bug 644452

I can also confirm this issue and solution with an Atheros AR9285 did by doing the following:

When right-clicking Network-Manager in toolbar, "Enable Wireless" is disabled. This option worked flawlessly prior to updating to Maverick RC on 10-6-10.

Tried the following in a terminal:
norlando@wooglin:~$ sudo ifconfig wlan0 up
SIOCSIFFLAGS: Operation not possible due to RF-kill
norlando@wooglin:~$ rfkill list
0: hp-wifi: Wireless LAN
 Soft blocked: yes
 Hard blocked: no
1: phy0: Wireless LAN
 Soft blocked: no
 Hard blocked: yes
norlando@wooglin:~$ sudo rfkill unblock all
norlando@wooglin:~$ sudo rfkill list
0: hp-wifi: Wireless LAN
 Soft blocked: no
 Hard blocked: no
1: phy0: Wireless LAN
 Soft blocked: no
 Hard blocked: no

At this point, right-clicking on the Network-Manager tool showed my wireless was now enabled, and in the process had actually had auto-connected to one of my saved networks!