Using 32-bit Mageia 3 clean install (everything but /home formatted) from the DVD (non-free stuff enabled) and a PCI card with a BCM4318 chip in my desktop. As I have since Mandriva 2010.0, I used b43-fwcutter to install firmware after the install. After rebooting, I attempted to use MCC's "Set up a new network..." but there was no SSID list on wlan0. There should have been at least two SSIDs, possibly three. Looking at Wireless in the Network Center, all three SSIDs showed after I hit the Refresh button. I configured a simple connection to my network (no encryption) and connected manually. The connection worked with no problems, and I was able to configure the mirror list and download software.
After shutting down and rebooting later, there was no connection again, until I used a refreshed Network Center to make it manually. I tried removing all the mga3 non-free firmware packages - same result. I tried using MCC to remove the wlan0 connection to try to establish a new one, but there was still no list in "Set up a new..." and the wlan0 "connection" had not been removed from the Network Center. As before, the Refresh button and manual connection worked.
No idea what to do from here, other than perhaps file a bug report. The b43 driver has always been usable with this device, and it still seems to be with Mageia 3 - once things are initialized manually.