Google has officially extended the search results snippets to a maximum character length of 320 characters. They confirmed with me late on Friday saying:

What are snippets? The description line under the clickable title and URL in the search results page:

Danny Sullivan, now at Google, also confirmed it on Twitter:

Google is telling webmasters to not go ahead and change their meta descriptions. Danny wrote “don’t go expanding your meta description tags.” He said the longer snippets are “more a dynamic process” Google automatically makes based on the content on that page and your query.

How long can those snippets be? Danny said a maximum of 320 characters. I believe the example above in the screen shot is a maximum of 307 characters but it can go longer says Danny.

Google has not yet made a statement about if they have changed their commendations for writing meta descriptions. Danny referenced a previous tweet from John Mueller of Google who said not to really make changes:

We will see – but now, don’t be surprised to see longer snippets. It is not just a test anymore.

Forum discussion at Twitter.