Contrary to the following comments, it appears that changes will only apply to mobile searches. I retain this post to correct my error which I will attribute to relying on the wrong sources.
Google is making a giant change this week that could crush millions of small businesses http://zite.to/1zzk4Jc
Google has decided to use whether or not websites adapt to mobile devices a factor in how sites are ranked. I fail to understand the logic in this as it assumes content should be consumed on mobile devices.
The more sophisticated way to do this would be to alter rankings as a function of the device used to conduct the search. I would think Google could figure this out as device detection is not a major challenge.
