On your marks, get set... Wait, did you geocode your marks? I hope so, because you only have the next week to enter the Location Wild Competition from NakdReality and SimpleGeo. The winner gets $2,500 and an iPad for creating the "most interesting location-based app."
Chart APIs are useful and popular, and Google knows how to do them well, so they're continuously adding more features and options for customization to their Visualization API. The Google Code Blog recently highlighted a few of the newest features.