It's the beginning of the month, so that means that the new numbers for just how many phones are running each version of Android have come out. Following the past trends, Gingerbread has seen even more growth, running over 50 percent of all Android devices that visit the Android Market. The legacy versions keep dropping as well, with Cupcake and Donut (Android 1.5 and 1.6 respectively) dropping to 2.1 percent of the total. We still don't see a very big uptick in Honeycomb, which has historically been a slower grower. With Ice Cream Sandwich now among us, this chart will be interesting to watch as we see which carriers and OEM's send out those timely updates.
Source: Android Developers