I guess Foursquare just made a lot of users happy. That is if what they say is correct, and this really was the most-requested feature. Anyway, Foursquare has just announced that users will not only be able to mention their friends when they check-in, but actually check them in as well. The new feature comes with today’s app updates for both iOS and Android.

Yep, when you’re checking-in, the “I’m with +” button used to simply tag your Foursquare friends. Now, it’ll actually check them in.

Foursquare’s going with a one-time approval setup for the new feature. The first time one of your friends tries to check you in, you’ll receive a notification asking for your permission. And once you give it, they can check you in at any time in the future.

Of course, Foursquare has added a bit of a safeguard in the form of an easy delete button to get you out of check-ins you don’t want to be in.

Also, your own personal check-in takes precedence:

“Did your friend beat you to the punch? If you check in at the same place, before or after the friend check-in, yours will be the only one we show. So you can always get your photo in, or tell everyone what you’re doing,” says Foursquare.

I agree with Foursquare that this will save some time, and I’m sure that plenty of users did really want this ability. But the pessimist in me is already thinking about all the times this could go wrong. You know that dumb friend of yours who doesn’t think it’s a problem to check into that certain, uh, club you guys often frequent? Well, he’s checking in. And he’s checking you in with him. It’s loud in there, and you don’t see the notification. That means you can’t delete it. People see this – unhappy people. Skip to six months later and you’re living in the streets looking like a walking Nick Nolte mugshot.

Dramatic? Sure. But stuff happens, man.