While not fully implemented, some are seeing this new functionality. When a search is done using a hashtag, such as the one performed below (#notprovided):
The hashtag search makes a lot of sense as Google continues to expand the usefulness and requirement of Google+. Along with the increased use of secure search throughout Google properties, Google has made it mandatory to have an authenticated Google+ account to comment and interact with YouTube videos. This new search function can be done using the regular search field but the result page changes. In place of the Knowledge Graph, the results for hashtags includes an active stream of results from Google+ by default. Below the live stream there are options to perform the same search on Twitter and Facebook.
Search for hashtags on Twitter and Facebook from Google?!?! Yes! That is a thing, but not so much as Google has indexed the content on these ‘competitor’ web platforms. When you select the links for either Twitter or Facebook, you are whisked away to the native search on these locations.
From the #notprovided example:
The Facebook link requires you to be logged in to use the Graph Search.
The fact that Facebook requires you to be logged in, offers it’s own search combined with the initial [not provided] push in 2011, the writing was on the wall that Google would move to make all searches SSL. A flurry of activity is coming out of the Google camp, some of it is great for marketers, some of it isn’t. But most of it is great for users.