VeriSign recently got back the results of some extremely interesting research. We commissioned a third party to compare the Netcraft SSL list to the Alexa 1 Million, which is Alexa's list of the one million most visited domains in the world. This research compared the number of domains using various brands of SSL and determined that GeoTrust is chosen by more of the world's million largest domains than any other SSL brand.
I recently wrote about the quick and dirty look that security blogger Nasko did at certificate market share while attempting to account for site popularity. It was a great idea, begging for complete, thorough execution, and the new Alexa-Netcraft index supplies that.