I forget if I posted on this before, but Chris Putnam has a released a
beta version of his bibliographic conversion tools. It now uses MODS
as its XML format.
He's done a really nice job with these tools: personal names and titles
are properly parsed (family/given, title/subtitle), character encoding
issues are handled gracefully, etc.
There are just a few remaining issues (such as the genre question).
So, currently personal reference formats in all the personal reference
manager products can be converted to MODS, and once he's stabilized
these tools, he'll offer conversion from MODS back to those formats.
I realize few people on this list work with this sort of data, but if
you do, it'd be worth testing and sending any bug reports.