Snapchat has introduced a new feature called "Snap Map" that does exactly what you'd think it does: shows you Snaps, on a map. You can move and zoom the map from city level all the way up to global level to see where people are, and you can see hot spots where multiple people are at the same place sharing.
You get to choose if you want to share your location with your friends, or you can go into Ghost Mode and keep things private. Snapchat says the app will only update when you open up Snapchat, rather than continuously track your movements.
This isn't necessarily a direct competitor to the more granular location sharing features that apps like Google Maps and Glympse offer, but it is helpful for keeping people inside of Snapchat rather than jumping out elsewhere to find out where everyone is.