More than 50 jiras have been added since the last release from the 0.8 line (0.8.1-alpha). More importantly, this branch has gotten quite a bit of testing, especially while running against Hive 2.0 and LLAP. At this point, I think we can drop the alpha monicker from the release - and mark it for public consumption. The APIs for pluggable services can be called out as unstable in the release notes.
Thanks - Sid