A70/60 Sensor Discussion

We know that these cams have the same size sensor. However, has anyone ever been able to confirm that the A70 gets 3mp from smaller photosites ... or whether the sensors are exactly the same except for the A60 running only the 1600x1200 mode that is a lower-rez option on the A70.

To me it wouldn't make sense for Canon to produce two completely different sensors for these nearly identical cams. If the A60 is a disabled A70, then theoretically we should be able to get the "less noisy" 1600x1200 pics out of the A70 in that camera's 1600x1200 mode -- along with better movies and the option of 3mp.

Thoughts?