Just last month Gregg Stewart outlined some key marketing opportunities that businesses can use via check-in services, mainly foursquare. Although foursquare pretty much pioneered the marketable check-in space, they’ve now got some hefty competition to worry about, i.e. Facebook Places. If this is the first you are hearing about Places, then you are a step behind the rest of the technologically savvy US population. Just last week, Facebook rolled out Places, which is a check-in application that will allow you to tell your friends where you are.

If you’re thinking, “so what, it’s just another check-in application,” please think again. This isn’t a small unknown player; what we’ve got here is one of the largest sites implementing a local strategy, which will definitely stir up the local search marketplace.

In his most recent ClickZ article, Gregg Stewart discusses how Facebook Places works, predictions on how it will stack up against the competition and most importantly, how brands and businesses can leverage this new service to reach local consumers.