Helm v3.0.0-rc.2 is a pre-release. It is to help gather feedback from the community as well as give users a chance to test Helm in staging environments before v3.0.0 is officially released.
The official changelog will come out with the v3.0.0 release. For now, you can see the commit changes from v3.0.0-rc.1 here.
Installation and Upgrading
Download Helm v3.0.0-rc.2. The common platform binaries are here: