Oh, Stephen - we've let you down! I'm sorry no one answered your question sooner.
It's tough to make a decision for you. Do you have any kind of preference? Canon is generally more popular here than Sony. In fact, Canon sells more digital cameras than any other company in the world (except Nokia - but that's camera phones).
Why don't you tell us what you want to take pictures of, what camera you have now, and how you narrowed it down to those two cameras. We need to know something more about you to help you decide. And in the meantime, here's a page that compares the specs of both cameras. Maybe that will help: