Gareth Lloyd has put together a brilliant visualisation of all geotagged Wikipedia articles.
Even more fascinating is this video, showing the data mapped out over time and space:
There are, unsurprisingly enough, quite similar patterns to those found in the maps that we made of Wikipedia biographies mapped out by century. Early concentrations in the Mediterranean, and then an explosion of interest in the rest of the world in the last few centuries. This data gives us a fascinating insight into just how spatially concentrated our knowledge of history is.