Was running #39, stock kernel. Turned on Wifi, phone locked up and rebooted. Got to homescreen, locked up, rebooted. Then a third time. The fourth time, I used the notification toggles to turn off wifi before it locked up, but it locked up anyway. Next few times, I was able to get to the Settings menu prior to lock up and saw that Wifi was still on "turning off..."
Downloaded #39-3. Wiped system, data, cache, dalvik. Flashed 39-3. Flashed gapps. Booted up, started doing my Market downloads, etc. Turned on Wifi. Reboot. Homescreen, reboot again. I am now in Recovery preparing to wipe and flash again and am afraid to turn on Wifi.