Optio question

[Steve Jolly]

Has anyone had the opportunity to compare the Optio S and the Optio S4? 
   AFAICT the cameras are pretty much the same apart from the sensor. 
Is the lens sharp enough to make the resolution increase worthwhile? 
Has the smaller pixel size of the S4 caused the noise to go up noticeably?

S

PS I'm not sure if this email is on-topic enough for this list, so I'll 
just say "I like bagels!"  ;-)