Actually, I dont care about particular features in 1.0. As far as I am concerned calibre will hit 1.0 when I feel like enough features have accumulated since 0.9.0 to justify a major version bump. Feature and stability wise, calibre could have been called 1.0 years ago.
I could just as well go to 0.10, but the advantage with 1.0 is at least there will be no more questions about when calibre will reach 1.0
My development style is not really roadmap driven. I just work on stuff when the urge moves me. When enough stuff accumulates, the major version number ticks over.