Yes, bugzilla is the right choice. Usually select 'visual editor' as the component, and the VE guys will triage them over to the Parsoid component if it's really our fault.
Reproducible bugs are much more useful than "odd looking diffs" though -- if you think you know how the odd diff came about, doing a standalone reproduction in your sandbox and describing how you made that happen in the bug report is much more useful than just linking to a random diff. --scott