Given that none of those things are important to me, and that threaded messaging is important to me, I suspect we have very different answers to that question.
That's fair. My question was fairly rhetorical, and a bit flippant.
We all have different requirements. I can understand that threading may be important to some, but feel that ignoring users and consistent notification defaults are on the same level.
In fact, seeing as how notifications are already implemented, I see the inconsistency (which has caused me to miss important messages on multiple occasions) as a bug, which should take precedence over a new feature.
But still, clearly many feel differently, and that's OK. :)