Yesterday location-based social network Foursquare rolled out a substantial upgrade to its platform. Foursquare 3.0 includes improved discovery, recommendations, and rewards for its users.

Those rewards are aimed at loyal Foursquare users who check-in regularly at a particular venue. So to make it easier for the quarter of a million some-odd businesses that have claimed their venues to offer these rewards, Foursquare has just announced an update to its Merchant Platform.

The update will make it easier to create campaigns and it is launching with several pre-set Specials, aimed at both attracting new customers and rewarding loyal ones.

These include Flash Specials - the first people who arrive after a certain time get a special discount; Friends Specials - check-in with three Foursquare friends, for example, to get a certain deal; Swarm Specials - check-in with a large group; Newbie Specials - deals for the first time you check-in; and of course, Mayor Specials.

The updated Merchant Platform - which will remain free - has also added some analytics, so that business owners can track the details about the frequency and time-of-day when Foursquare users check-in at their location, and so that they can track the performance of the various Specials they offer.