Pentaho Labs is a way to show progress and get feedback on certain development projects. They are NOT supported product and in most cases, not even on the Pentaho roadmap. The purpose of labs is to do some preliminary work and get feedback from the Pentaho ecosystem on whether there is sufficient interest to continue development or put on the official roadmap. This fulfills the open source early and often mantra.
The projects identify their status, whether they are on a roadmap and what JIRA cases if any apply.