It looks like Penguin, but it's broader in its scope so at this stage it appears to be a multi-purpose update encompassing a range of search quality parameters. From webmaster reports we know this update carries global impact.
Link Spam
Some shocking websites have suddenly appeared in Google's results (anchor text manipulation, link networks) so it appears as if the update hasn't rolled out completely. If it has... well then it's a likely failure and it will have to be rolled back much like they did in December 2014.
Localisation
There are still hints of this being localisation related change as well (some websites are now showing double listings classic organic and local organic).
Snippets
Certain results now show longer, very detailed snippets which often disregard meta description. These appear to a limited audience, likely a test.