Wikimapia is great service with the aim of adding information like title, notes, photos and comments to all interesting locations on Earth. It currently has over 10,000,000 places marked. Unfortunately its Google Maps-based interface is deadly slow in Safari on iPhone.
And here WikiPlaces comes to help you. It uses publicly available KML feed from Wikimapia to overlay its objects over standard Google map. You can find very interesting information about places near you and all over the world. Anywhere it will be either helpful or just fun to play with.
