You may click on the button above to watch her talk, but this is one TED lecture I really recommend watching in its high-resolution version, if you have Quicktime or Windows Media Player installed. The stunning images of Saturn which she shows at the end can best be appreciated in that format.
There is a brief biography of Carolyn Porco on the TED site, and Wikipedia's article on her is here. There are websites for the Cassini Imaging Central Laboratory for Operations, and also for the latest images and news from Cassini, including a virtual tour of Saturn in 3-D. (The last requires installation of an add-in to your browser.) All are well worth your time.