sudo apt-get install bcm43xx-fwcutter
sudo apt-get install network-manager-gnome
at which point (perhaps after a modprobe but rebooting should also do) my WiFi just started working. There are two important things to note: (1) Ubuntu apparently likes it better when you boot with the hardware switch (on the left-hand side of the lapgtop) for WiFi in the on position; (2) running the DHCP client on two devices is apparently not what Feisty wants, so deactivate the wired connection when you want to use the wireless one. At this point I started updating the system and here hit a serious but short-lived hitch: after upgrading the kernel to 2.6.20-14 my system would no longer boot into Feisty. Of course, I just booted to the old kernel and in fact the problem was solved the next day by the release and installation of kernel version 2.6.20-15 which I am using to write this post. With Automatix2 I installed some naughty things like GoogleEarth and xDVDshrink effortlessly and right away!