Charts tell the story of our data, so we often spend a lot of time getting the formatting just right. That’s why we wanted to make that process quicker and easier in Google spreadsheets. Instead of opening the chart editor dialog to make formatting changes, you can now click directly on the part of the chart you want to modify to change things like the colors, legend, and labels.
(Hat tip to the Free Technology for Teachers site for first alerting me to this. Go here: http://www.freetech4teachers.com/2012/09/one-click-chart-editing-in-google.html#.UFl5go3ibU0