Danny Sullivan goes over the major differences in Google Authorship - well worth the read.
In Short. It doesn't affect your rankings. I have not seen it affect any of my sites they all rank the same, and now with the authorship snippet out of search there really doesn't seem to be much incentive. I would say that in the future I will probably hold more weight and it definitely worth cultivating a strong Google plus profile... who knows how much it will help in the future.
Google plus can drive targeted traffic if harnessed correctly so regardless of the impact it currently has on your rankings you should definitely be using the platform to drive target traffic to you site.
Google Authorship May Be Dead, But Author Rank Is Not http://ift.tt/XYZENN