Hello fiddy and everybody,
Just some information for comparison from here. I also am using b43.
[boo@localhost ~]$ iwlist wlan1 rate
wlan1 unknown bit-rate information.
Current Bit Rate=54 Mb/s
I used b43-fwcutter to extract the firmware myself from wl_apsta_mimo.o acquired from broadcom-wl-126.96.36.199.tar.bz2 available at openwrt.org
. That's not the newest version of the Broadcom driver tarball available at openwrt.org, but I've been using it since Fedora 9 and will keep using it until it stops working. I don't know what version of the driver tarball Dangermouse's things (Autoten, Broadcom RPM) use, but they do use the wl_apsta.mimo.o file. That's what you are using, fiddy.
Other factoids from here...
I'm using a Linksys WMP54G PCI card and two Linksys WPC54G PCMCIA cards to connect to a Linksys WRT54G wireless router thirty feet and two walls away. I use WPA encryption with a 16-digit ASCII passphrase. All report 54 Mb/s bit rates (occasionally 48 Mb/s rates, but I rarely check). Strong neighbor signals, too. Easily connect at hotels and public hot spots with a Thinkpad with Fedora/Debian/Ubuntu/b43/NetworkManager.
A little history kinda...
In the past, I have used the bcm43xx driver which was the original reverse-engineered Linux driver for Broadcom devices. That project started back when Broadcom was giving Linux nothing. It eventually evolved into b43. The bcm43xx driver shipped with Fedora Core 5, 6, and 7. In the middle of the Fedora 7 life cycle, bcm43xx was replaced by b43 in the Fedora kernel modules. Broadcom eventually produced the an open source driver for Linux (aka broadcom-wl), but as you know, it doesn't work with your particular Broadcom chipset.
Farther in the past, I've also used ndiswrapper and bcmwl5.sys from Windows for those same devices. I've installed ndiswrapper from both source and the binary kmods from Livna and, later on, RPM Fusion which took them over from Livna. They all worked fine. In fact, for a while I would drift back and forth between ndiswrapper and bcm43xx (and later on, b43). I tired of compiling source, so I mostly used the kmod version of ndiswrapper. The kmods worked well, but they would be late arriving in the repos sometimes which busted wireless when a new kernel came along. The last time that happened, I just sort of snapped and went back to b43 for good. And here I am now with it still.
I guess the point of all this (besides FYI), is to try stuff. Try both ways. Try a different version of the Broadcom tarball for b43. But remember, these things can conflict with each other leaving nothing working, so undo or blacklist and unblacklist as needed when you switch driver methods or else an unholy mess will occur.
If you would like to try extracting the firmware manually yourself someday, here are the steps that I use. Remember to delete the old firmware files in /lib/firmware/b43 before extracting new firmware to there...
tar xjf broadcom-wl-188.8.131.52.tar.bz2
b43-fwcutter -w /lib/firmware wl_apsta_mimo.o
I don't extract the firmware any more. I just copy the same files in /lib/firmware/b43 over to each new Fedora version.