I've used Fedora 17 on my Pi for some time and it works well although there are some problems.
My experience is detailed in this post and this follow-up.
Well, Fedora 18 has been available for a while now and a RPi version also appeared thereafter, so it's time for an upgrade.
However, rather than a clean install, I first tried upgrading from a terminal.
This is well documented in the Fedora wiki where two methods are suggested.
The recommended method is to use FedUp which is more beginner-friendly.
Unfortunately, although the app is available for use on the Pi, it doesn't work primarily because the methodology invokes the Grub bootloader to complete the upgrade.
However, there's no Grub on the Pi and no workaround seems to be available.
Ok, how about the Yum approach to upgrading Fedora to 17 to 18 which is detailed in the last link.
Unfortunately, this approach also didn't work on my Pi due to many errors.
Nothing for it but a clean install using the compressed image found here.
This went very smoothly and I used Gparted to increase the /root partition to take up all remaining space on my 8GB Sandisk Extreme Pro SDCard.
Note that as the image includes a 512 MB folder called /swap0 which serves as a swap partition, no further partition is needed on the SD Card.
As I had not installed over my Fedora 17 install, I was able to copy all essential stuff (mainly my elaborate Conky setup) from my old Fedora to the upgraded version.
Fedora 18 uses the xfce4 DE as before but the default DM has changed from GDM to LightDM.
However, although it's well-documented, I could not get lightdm to autologin by editing /etc/lightdm/lightdm.conf
Even invoking /etc/pamd/autologin did not work for me on the Pi.
I hate having to enter a password every time I boot into an OS so the lack of autologin in xfce4 forced me to look at the Fluxbox WM which I had recently played with in FreeBSD on my Pi
In summary, Fluxbox is wonderfully light, yet feature-full and ideally suited, I think, to the low resource boxes like the Raspberry Pi.
I could write pages on what I've done but because I'm short of time (traveling again tomorrow), I'm just going to summarize the main points of my experience so far.
i) Absolutely no problem getting Fluxbox to aulolog me in.
The three steps were:
a) to the file ~/.xinitrc add the line
exec startfluxboxto start the WM at boot.
b) add the line
[[ -z $DISPLAY && XDG_VTNR -eq 1 ]] && exec startxto ~/.bash_profile to start the X server at boot.
c) follow these excellent ArchLinux instructions to autologin your user at boot.
Actually, although I'm using Fedora 18 (the version I'm using is called Pidora 18), all of the references I've made to get complete autologin to the X desktop came from ArchLinux documentation.
ii) Conky works perfectly on Fluxbox in Pidora 18 with none of the transparency problems I had in xfce4.
The .conkyrc file I use is exactly the same as I had previously used in Fedora 17 on the Pi.
Additionally, there's no loss of transparency of the Conky window when new mail is received.
iii) Setting your Desktop wallpaper is very easy.
Unfortunately, when I wrote this the fluxbox wiki was down which restricted what I could reference.
However, a very lightweight configuration guide is also available here.
I added the following line to the ~/.fluxbox/startup file to get my selected wallpaper to load at boot time.
fbsetbg -f /home/paul/Pictures/fluxbox/fluxbox_wallpapers_by_deviantvicky-d33ory3.jpg
Well, there's still a lot more to report but it'll have to wait as I've run out of time for the moment.
But, I'll complete this post in just over a week's time.