People match one another’s language

People match one another’s language when speaking and do it more so when they’re happy:

“When two people start a conversation, they usually begin talking alike within a matter of seconds,” says James Pennebaker, professor of psychology at the University of Texas at Austin. “This also happens when people read a book or watch a movie. As soon as the credits roll, they find themselves talking like the author or the central characters.”

And:

Because style matching is automatic, it serves as an unobtrusive window into people’s close relationships with others.

Astoundingly (and perhaps implicit in our behavior), this idea can be used to reveal something about future partners:

Style matching has the potential to quickly and easily reveal whether any given pair of people — ranging from business rivals to romantic partners — are psychologically on the same page and what this means for their future together.

Does style matching extend beyond language to fashion? To food? To travel preferences? It would explain a great deal.
>> more at: http://www.futurity.org/society-culture/language-a-bellwether-for-compatibility/