Look at the CICLOPS image o' the day
here.
Blow up the JPEG, PNG, or TIF file.
Notice the shape of Pandora -- oblong.
This in of itself might not mean much, as it is a small moon, not massive enough to generate tidal forces to make a sphere. But... what if this shape is caused by added material from the F-ring, causing a bulge around its equator. Hmmm???
The same theory was put forth to explain Iapetus' ridge -- material taken on from the rings.
Note: this isn't a post-and-run. I just realized I made it late Friday. I'll have to wait until Monday morning to enter discussion. Have a good weekend, all.