Along with being negligent on the roadmap sort of things, I fell behind
keeping the issue tracker updated. I've now gone through and WONTFIX'ed
anything unnecessary in rustboot, adjusted text of bugs that have
changed, closed those that have been fixed but not otherwise closed,
shifted bugs that apply equally to the two to rustc, and filed a bunch
of new feature work on rustc.
If you want to focus on things required for bootstrapping (aside from
driving your work off the testsuite and/or 'make self'), take a look at
the bugs tagged [rustc] and [self]. Self in particular, since those are
the ones actually blocking self-compilation.