Hardy Heron, Ubuntu 8.04 beta
Well, no surprise, I broke a few things, though surprisingly, it's a pretty small list. Going from Gutsy Gibbon to Hardy Heron on my Vostro 1000 was very smooth, and required very little effort to get it up and running again, for the most part.
Compiz (3d graphics): Well, no surprise, It was somewhat of a hack to get it going on my laptop, originally, but the only thing that broke during the upgrade was a weird error about gnome-settings-daemon not being able to start. The fix:
sudo apt-get remove xserver-xgl
Unfortunately, I'd tried someone else's fix of blowing away all of the .gconf, .gconf2, etc settings in my home directory, which obviously didn't help, but now has me reconfiguring all of my settings... oh well. Just use the line above, and save yourself some of the pain.
However, removing xserver-xgl will probably kill your ability to run Compiz, and you may need to turn composite on in your xorg.conf file (/etc/X11/xorg.conf). That can be done by finding the lines:
Option "Composite" "0"
and changing the "0" to "1". Tada, Compiz works again!
Wireless: This one was interesting: there's a new driver for the wireless card, so it tries to install that over what you've already got going. The new driver is much better than the old, so its a good thing, but you still need the (not-open-source) firmware from broadcom. Installing it couldn't be easier.
Follow the first 3 lines here to uninstall ndiswrapper, if you had it running before. (You don't want the new driver running at the same time as the old: this may mean you might want to take the out any lines saying ndiswrapper or bwcml43, or similar from /etc/modules.)
Follow the instructions here, to install the b43 driver firmware, although my simplified version would be:
sudo apt-get install b43-fwcutter
tar xjf broadcom-wl-22.214.171.124.tar.bz2
b43-fwcutter -w /lib/firmware wl_apsta.o
You'll notice I've skipped a few steps compared to what's on the linked page. "b43-fwcutter" can be installed through apt-get, so there's no point in building it yourself, and /lib/firmware is the right place to put the firmware in Ubuntu, so you don't need to be fancy about exporting it and then using a shell variable. And that did it for me.
You may also need to go to System->Administration->Hardware Drivers to tell Ubuntu to use the b43 driver. After that, my FN+F2 key works again, and I was able to connect to my wireless network.
All is good again with my laptop.