All the splits
First of all, here is the table published by the IAAF this morning, containing all the splits and times for 20m intervals, for both the semi-final and final:

Next up, some graphs to highlight certain things a little better. Below is a graph showing the 20m interval times for the top 3: Bolt-Gay-Powell
It reveals how Bolt achieved the fastest split at all intervals, which is amazing considering his supposed slow start. He led the race at 20m, and continued to grow that lead. I have shown his times on the chart:

The relatively slow first 20m (because of the start) makes interpreting the last 80m of the race quite difficult, so I've taken the liberty of looking only at the last 4 intervals, for a more obvious comparison between Bolt, Gay and Powell. It makes the point that Bolt was dominant from start to finish, as shown below.

Translating those times into speeds is a simple but interesting exercise (shown in the graph below), because you then perceive just how fast the top end speed is. For Bolt, the fastest interval (60m to 80m) was run at an average speed of 44.72km/hour. If you're wondering how that compares to last year in Beijing, read on...


Here is the link to get more info -  http://www.sportsscientists.com/2009/08/analysis-of-bolts-958-wr.html