When Tweeters Got on the Twitter Train

I wanted to close out the week with an interesting timeline of when notable Tweeters got on the "Twitter Train". WhenTheWhat has become one of my favorite new sites and once again put together a heck of a chart. Do any of these users put Dollar Signs in their tweets? Perhaps an idea for a future timeline....

This is the 2nd time I put up one of their timelines. Here is my personal favorite. I would frame this one in a heartbeat - A History of Baseball's American and National League Teams