Booting rawhide's vmlinuz and initrd.img, I'm unable to choose which interface the net installation should use. Using Fedora 10's initrd.img, the installer askes me "You have multiple network devices on this system. Which would you like to install through?" so I can choose between WLAN and LAN. (I cannot use WLAN because the installer does not seem to support WPA)
What network devices do you have in the system that you are expecting to see in the installer list?
WLAN: Intel 3945 abg LAN: some Marvell 1Gb/s card
So the installer is only seeing one network device, the wired device? Can you perform an installation and collect the log files from root's home directory after installation? Attach the log files to this bug report so I can get a better idea of what's going on. You should see install.log and install.log.syslog in root's home directory after installation.
So I finally re-installed the system. The problem did not occur... but now I realize that I used rawhide's vmlinuz and initrd.img last time and F11A's today...
Closing per comment #4. Rawhide changes daily. If you aren't able to test rawhide on a daily basis, stick with the alpha and beta releases and report based on that. F-11 beta will be released soon, so I'd recommend trying with that to see if the problem occurs again. If so, reopen this bug.