What do they say? How do they say it?
Tweets are limited to 140 characters, but do people use that full amount or send shorter messages? The histogram to the left shows tweet lengths across our dataset. As you'd expect there's a spike near 140 characters but very few people actually make sure to use all the characters available to them.
Tweets can be geo-located, but do people actually use this feature? The pie chart to the left shows the ratio of located tweets (either at a specific place or just a lat-long point) to those without. As you might expect celebrity tweeters tend not to broadcast their whereabouts.
Surprisingly a large number of tweets come from the web site, not via third party tools (although this is dominated by @justinbieber). It seems @stevewoz pretty much only tweets via Foursquare.