Well there are |Distributions X bootLoaders| possible combinations.
I would argue to get something like a "standard" here ;)
No, really, someone should (at least at the grub level) find a way to
identify the boot partition with some metadata.
Anyone from our developers going to FOSDEM and meet some of the other
distro guys?
If all (or at least the most) distros agree on one boot partition
metadata standard, implementation should be easy.