: 1. For most practical purposes, 0.6.x contains more features and minor bug fixes and upgrading should be smooth. A subset of the differences are described in the CHANGELOG (https://github.com/scalapb/ScalaPB/blob/master/CHANGELOG.md
) - unfortunately I haven't been updating it consistently. The reason we moved from 0.5.x to 0.6.x is the breaking change related to custom options and custom extensions (something most people don't use), which is described in the CHANGELOG.
- Soon (probably less than two weeks). We have all the features I wanted merged. You can think of 0.6.0-pre5 as a release candidate.