Going to describe this entry a bit later, but in short "ubuntu server edition can't be plain installed on a server via serial console connection, but with custom made iso/cdrom, which is not always an option".
don't discuss this entry here, better go to bug-report URL and put your thoughts there.
2) how useful is "splash image" bootloader option for servers, which are managed over a serial console? Every time I'm removing it, a usual update to server kernel which is upstream distributed (via aptitude/apt-get upgrade) insists to add it again and again. Don't ask me about "serial console", because almost all branded servers has it, i.e. HP ilom, IBM rsa, SUN sp/lom, DELL drac, etc...
3) going to post update on "installation over serial console" later.