Have you used Foursquare recently? While it originally focused on broadcasting one's location, it's more about social recommendations now, which really isn't fa

Have you used Foursquare recently? While it originally focused on broadcasting one's location, it's more about social recommendations now, which really isn't far from "social map annotation" in practice. Especially when you have people leaving notes in parks and bridges and buildings telling you about neat features and not just "the denver omelette is amazing here!"