Comment # 9 on bug 948555 from Olaf Hering

(In reply to Michael Chang from comment #8)
> IMHO, the 'ro' is the right thing to do if you want to run fsck on boot
> otherwise file system faults may not be recovered. So that we should leave
> it as default than 'rw', and if we really want 'rw' boot option we should
> specify it on GRUB_CMDLINE_LINUX= or such to override that default (ro).

Its up to the initrd to do that fsck for us, when nothing is mounted. If one
really wants a read-only mount the 'ro' exists for that purpose. Too bad
upstream does not understand booting...