I noticed OpenLandmark when I was looking at the mobile apps for the iPhone/iPod Touch. It is a beta site that is creating a directory of landmarks, currently focusing on a few cities, which are mostly major tourist destinations. It is similar to a few other projects out there, except that it seems to be a cleaner approach than the straight wiki map sites. The OpenLandmark page talks about geotagging, photographs, discovering and contributing and it seems fairly interesting as a beta though I want to see what happens after it has been around for a few months. I will check it out again the next time I am in one of the cities that have been built out so far.