The big drag on the Facebook's IPO was the revelation that they don't really have a plan to monetize mobile users. The trend is clear that people use Facebook on their phone, reporting and checking in from big Milwaukee festivals and their local haunts. That location data is central to Facebook's plan for the future.
The Verge has the details on the plan. They're light on details for the actual execution of this model, but you can be sure that it's going to tie into the check in model. I am not sure exactly how they can build this experience in a way that's unique. Take over ads after checking in? Deals worked out with local vendors? These seem like strategies for Foursquare not Facebook.
The big red flag for Facebook in this plan, and that's turning what you do into aggregate data for the highest bidder. Most people already feel like they're always fighting with Facebook for their privacy, making your Smartphone into a tracking beacon for advertisers might not go over that well.
Facebook needs to do something to ensure that it stays ahead of user trends. It seems that more people are waiting for them to announce a monetization plan than announce new features. That might just be a sign that people are invested in the company's survival, or they just expect nothing else from the company's near monopoly over social networking.