The who is the owner of '' has recently shared a post in his G+ account that, While he searching "
vine videos community" in Google, his G+ Community has been showing as #4 position and It links to the Discussion category of his "
Vine Videos - A 6 Second Video Community" on G+. If he search for "
vine videos discussion," it comes up #1.
This means, Not only can individual posts in public Google+ Communities be indexed by Google search, but the Communities and even categories inside Communities can be indexed as well.
Also here is an another interesting post regarding Google+ Communities Indexing
