Open up your mind and say, ahh...

Foursquare tells people where you are. A new mobile app called Forecast, which is opening to Facebook users on Tuesday, instead tells them where you will be.

Here’s how the free app for iPhone and Android works: Users make “Forecasts” that include what they plan to do and what time. Those Forecasts are broadcast to their friends, and can serve as informal invitations to join.

Friends can accept them by clicking a “me too” button, and when they arrive, they can check in the same way that they do on Foursquare. Pinnell says more than 80% of forecasts are followed through to the check-in.

“The special thing about the future is that it hasn’t happened yet,” explains CEO René J. Pinnell, “which means you can change it.”

This thing is especially special to advertisers.

It’s the reason that Google makes so much money off of search ads. When advertisers can reach people at a time they are making a decision, like searching for a dentist or declaring their desire to go out for pizza, they can influence that decision. Targeted deals and suggestions for complementary activities are both business models that work nicely with the future checkin.

For this reason, Forecast isn’t alone in its pursuit of what I call the “preemptive checkin”. Ditto, Hotlist and Crowdbeacon are just a few others.

None of these, however, dominates the concept in the same way Foursquare dominates the real-time checkin.

 

The group messaging battle just heated up with the announcement Sunday that Skype has entered into a definitive agreement to acquire GroupMe, a group messaging service that will enhance Skype’s ability to facilitate text and photo messaging.

With this acquisition, Skype said in a press release that GroupMe will provide “best-in-class text-based communications and innovative features that enable users to connect, share locations and photos and make plans with their closest ties.”

Given the hyper-competitive backdrop of this booming group messaging field, it’s no surprise that Skype’s CEO Tony Bates told The Wall Street Journal about how important he thinks the mobile group messaging space is to his company. That’s evidenced by the multiple deals in that space taking in the past year, including Google’s purchase of group messaging company Slide in August of last year, Facebook’s rollout of its Group Chat capabilities after it acquired group messaging app Beluga in March of this year, and Apple’s June announcement of iMessage in iOS 5 that’s also capable of group messaging.

Even though Skype agreed in May to sell itself to Microsoft for $8.5 billion, that transaction has not been completed yet. Skype’s CEO didn’t specify the terms of the agreement between Skype and GroupMe, which is expected to close on Monday.