Anyone who’s ever been to an important sports game, the showing of a cult movie, or a meetup between car owners has probably observed that a single common interest can sometimes make people the best of friends.  And now, Twitter’s preparing to capitalize on that fact by testing a "You both follow" feature.

At the moment, something like ten percent of Twitter users should be able to see the words "You both follow" and a collection of other users’ profile pics when they view certain profiles.  (All of this appears right above the standard "Following" section.)  This is just a straightforward way of showing what connections people happen to share.

It looks like a lot more people will soon be able to see when other folks share their affection for, say, Conan O’Brien and BPGlobalPR, too.  Twitter engineer Nick Kallen, who provided the ten percent figure with one tweet, admitted in another that testing was expanded to involve 100 percent of users for about five minutes last night, which implies that a full launch will occur sooner rather than later.

Anyway, a hat tip goes to Chris Pirillo, who expects the rollout to take place "within the next day or two."

A significant uptick in activity on Twitter will probably then occur as a result.