Google's introduced one of its biggest-ever changes to search, tapping Google+ results to give more personal results in a move that some observers suggest may contravene US anti-trust legislation.
Titled Search plus Your World, the new service, being rolled out over the next few days to English speakers, builds on Social Search to highlight personal content from users and their friends.
It also makes it easier to find profiles in search. "Now, typing just the first few letters of your friend’s name brings up a personalized profile prediction in autocomplete," says Google fellow Amit Singhal on the company blog.
"Selecting a predicted profile takes you to a results page for your friend, which includes information from their Google+ profile and relevant web results that may be related to them."
And a new People and Pages feature offers a list of 'prominent people' who regularly discuss a given topic on Google+ so that searching for 'music', for example, offers you pearls of wisdom from the likes of Britney Spears and Snoop Dogg.
However, Twitter's senior lawyer, Alex Macgillivray, describes the move as a 'bad day for the internet' in a tweet.
"Having been there, I can imagine the dissension @Google to search being warped this way," he says.
By highlighting Google+ results, says Twitter, the company is effectively demoting content from its competitors. And there's no clear reason why the People and Pages feature can't offer Twitter and Facebook accounts as well as Google+, for example.
Rather smugly, Google points out that it no longer has access to the Twitter database, making it hard to screen results effectively for relevance.
"We are a bit surprised by Twitter's comments about Search plus Your World, because they chose not to renew their agreement with us last summer... and since then we have observed their rel=nofollow instructions," it says on the Google+ blog.
Let's hope for Google's sake that's enough to satisfy regulators.