Another tidbit coming out of the Google+ hangout yesterday is that Google confirmed the mobile-friendly algorithm being released on April 21st is a yes or no / on or off factor. Either you are mobile friendly in Google’s eyes or you are not, there is no level of degrees of mobile friendly.
Google’s Mary said at the 47:10 mark:
They go on to explain that UX is important in general so get to it.
Forum discussion at Google+.