Why has wireless disappeared after my 12.10 upgrade?

I just upgraded to 12.10 on my Lenovo B570 laptop. NetworkManager isn't displaying a submenu for wireless connections at all, even though I downloaded the update through the wireless connection. This displeases me.

Stuff I've tried includes:

$ sudo modprobe wl
FATAL: Module wl not found.
$ sudo lspci -nn | grep "BCM"
02:00.0 Network controller [0280]: Broadcom Corporation BCM4313 802.11b/g/n Wireless LAN Controller [14e4:4727] (rev 01)
$ rfkill list all
0: ideapad_wlan: Wireless LAN
        Soft blocked: no
        Hard blocked: no

ETA: linux-headers-generic is already the newest version, and what I get when reinstalling bcmwl-kernel-source includes the following, near the end.

DKMS: install completed.
ERROR: Module b43 does not exist in /proc/modules
ERROR: Module b43legacy does not exist in /proc/modules
ERROR: Module ssb does not exist in /proc/modules
ERROR: Module bcm43xx does not exist in /proc/modules
ERROR: Module brcm80211 does not exist in /proc/modules
ERROR: Module brcmfmac does not exist in /proc/modules
ERROR: Module brcmsmac does not exist in /proc/modules
ERROR: Module bcma does not exist in /proc/modules
FATAL: Module wl not found.

ETA2: Solved! Turned out the problem was that I'd been running the 3.0 kernel instead of 3.5 -- meaning the seeds of this problem have been lurking around for at least half a year. chili555's answer helped me discover this, though it took a little longer to find out how to boot to 3.5.

Solution 1:

Please hook up the ethernet temporarily and do:

sudo apt-get install --reinstall linux-headers-generic linux-headers-`uname -r`
sudo apt-get install --reinstall bcmwl-kernel-source
sudo modprobe wl

The backticks are on the left side of my US keyboard on the same key with ~. It it working now?