If you click on a Clustr Map, such as the sample one on the Clustr Map website itself, it is enlarged and gives you more statistics. The statistics include which number of visitors from each country and state. It also shows the information about where the most recent visitors were from.
SlideShare presentation. Students would be motivated by the increase in audience and also learn some geography at the same time. Tom Barrett, in his blog post, also strongly suggests that you include a Clustr Map on your class blog as helps students to realize they have a real audience.
I added a Clustr Map to this blog as a demonstration. At first, no dots show on the map. Over time, this will increase. See if your dot shows on the map!