1.0.0 sounds good to me. Maybe we can target 1.0.0 after this 0.6.0 release. I think we'd better not rename the incoming release from 0.6.0 to 1.0.0, because it contains many new changes and may take some time (+ bug fixes, if any) to get stable. I would rather see a stable 1.0.0 release with few new features than an unstable one with many new features.
