Since upgrading to 12.10 while it was in beta, I have been unable to connect to wifi, which I was able to do while using 12.04. My laptop is an Acer extensa 5635z.
Maybe fwcutter would help
To install fwcutter:
It mainly works for BCM hardware
You can also install fwcutter legacy driver if you are unable find them. Unfortunately you will need to google it