That makes sense - you have the broadcom wifi, many 6450b appear to have an intel centrino .
Your device wasn't "claimed" by any drive at bootup.
I'm not the broadcom wifi expert, but it appears that this driver is not included in Fedora undoubtedly b/c it's non-free code. ((Fedora is all free code)). Some other distros like Ubuntu aren't so picky.
The driver is available in the rpmfusion repository, here:
Click thru the "enable rpm fusion ..." and use either the firefox or the command line setup. This step enables your system to access the RPM-fusion repository.
Onec that is setup then install the package: "broadcom-wl" using the command line:
yum -y install broadcom-wl
After that then reboot. Then "lspci -nnk" should show a "kernel module" for the wifi, and NetworkManager" should recognize and use your wifi.
*** IMPORTANT *** The yum command above will also pull in the "kmod-wl" package which is a driver, while broadcom-wl are just some config files. Whenever you updsate the kernel you will need to update the driver package as well.
Here is the package descriptor,
Name : broadcom-wl
Arch : noarch
Version : 126.96.36.199
Release : 1.fc13
Size : 12 k
Repo : rpmfusion-nonfree
Summary : Common files for Broadcom 802.11 STA driver
URL : http://www.broadcom.com/support/802.11/linux_sta.php
License : Redistributable, no modification permitted
Description : This package contains the license, readme and configuration files
: for the Broadcom 802.11 Linux STA Driver for WiFi, a linux device
: driver for use with Broadcom's BCM4311-, BCM4312-, BCM4321-, and
: BCM4322-based hardware.