A lot of people contributed some really great feedback about MozReview at Whistler. One of the most frequent requests was for the ability to publish submitted review requests without having to open a browser. I'm pleased to report that as of yesterday, this feature is implemented! If reviewers have been assigned to all your review requests, Mercurial will now prompt you to publish the review requests during hg push. It should just work.

As part of this change, we also introduced more advanced feature negotiation into the handshake between client and server. This means we now have a mechanism for detecting out-of-date client installations. This will enable us to more aggressively drop backwards compatibility (making server-side development easier) while simultaneously ensuring that more people are running modern and hopefully better versions of the client code. This should translate to moving faster and a better experience for everyone.

http://gregoryszorc.com/blog/2015/07/07/publish-when-pushing-to-mozreview