Fairly new install on my Macbookpro 6,2 laptop with Ubuntu 12.10 32bit(idk why I did 32 and not 64). My wireless would randomly drop internet (it would stay connected to my router, but lost internet connectivity). To fix this I tried using the b43 driver (sudo apt-get install firmware-b43-installer b43-fwcutter, and also I tried form the software center). At first I thought it was working from there but I never made sure that the OS used b43 and not brcmsmac.
So I added bcma and brcmsmac to the blacklist (/etc/modprobe.d/blacklist.conf) and adding b43 to /etc/modules. Next I ran 'sudo modprobe -r brcmsmac bcma' which successfully turned off my wireless card. After that 'sudo modprobe b43' failed to turn on my wireless card.
'lspci -vnn -d 14e4:'
Boradcomm Corporation BCM43224 802.11a/b/g/n [14e4:4353] (rev 01)
Subsystem: Apple Inc. Device [106b:0093]
http://linuxwireless.org/en/users/Drivers/b43 says b43 works for my BCM43224 card as well. I might have messed something up when trying to uninstall and reinstall b43 before trying out the modprobe commands, but I don't know if something like that would be possible or not.
EDIT: And after running 'sudo modprobe b43' it does show up in lsmod.