The scores on both charts are calculated from user results uploaded to the Geekbench Browser. Each score is calculated by averaging the results for each device. Note that a device's score is only reported if there are five or more results for in the Geekbench Browser. Currently there are 31 different Android handsets and tablets on the Android benchmark chart, while all of Apple's iPhones, iPads, and iPod touches are on the iOS benchmark chart.
I think you'll find the two new charts useful, either when you're purchasing a new handset, or when you're determining if your current tablet's performance is up to par.