I’d like to be able to up/downvote WPs (e.g. features or user stories). A good example would be this forum/bugtracker here. This would help developer to identify the communities interest.

Bitbucket (but not Github) has implemented this feature already: https://blog.bitbucket.org/2013/08/14/no-more-1s-bitbucket-issues-now-has-voting/ Begin of the insertion
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