TweetMondo works better the more precise your list your own location. It allows you to find others in your area as well as them to find you, depending on privacy systems.
You can see the number of people in a location, but not details until you log into the site itself. I used a test account and tried out the local city.
I did not like the fact that they forced you to post a tweet that you are using the service and followed them automatically. Make it a freaking choice if I like your site or not.
Once in the map did show avatars of other users in the city. I can see how the more precise you are it would zoom in tighter showing people very close in proximity. Ads by Google show in the corner of the map for their revenue.
Hovering over any avatar didn’t not give details but I found a list at the bottom of the page. You can click to show the person on the map, see how percise they list their location (by percentage) and their basic bio info such as followers and how many tweets sent. You can follow and send a message to anyone on the list as well as see how long ago they were on.
The right side allows you to filter by name, bio, precision level, number of followers or minimum number of tweets which was quite helpful. I found that if they use a client that updates the geo location then it gives an excellent precision percentage.
I liked what they were doing and it was good to see people in the immediate area to find or follow. I will be back (if they fix the auto follow and posting).
There were some privacy settings on if you should show in searches on the sites as well as some basic profile questions.