We've recently launched a local Twitter Directory - http://www.loadedweb.com/twitter/ Unlike other directories, instead of just listing users, we are trying to make sense of what people are talking about - if a topic (or link or @user) is popular in NYC - is it popular in LA? In Houston?
An interesting example is NYC: http://us.loadedweb.com/twitter/new-york/new-york/ - eg you can see that @jimmyfallon and @guykawasaki have been consistently popular in the last week and last month. On the other hand, @nytimes has gotten popular in the past week while invisible in the overall month, with Newyorkology popular in the past month but not the past week.
Still - this is just a start. With more users will come more interesting information - and we will continue to develop it out to extract other localized trends.
At this time, we support US, Canada, UK, Australia, and New Zealand.
Any questions, let me know.
-Lesley
www.twitter.com/geopants
