Canon announced a service advisory regarding oil on the sensor of the two above cameras. ; Apparently when you're taking pics at 10fps oil can fly off the kevlar shutter blades and land on the sensor, so they'll clean it for free.
Anyway, take a look at their link, it has a good pic of what a VERY small oil drop looks like on a sensor.
http://www.usa.canon.com/consumer/contr ... 2&id=57853
Anyway, take a look at their link, it has a good pic of what a VERY small oil drop looks like on a sensor.
http://www.usa.canon.com/consumer/contr ... 2&id=57853