I wouldn't think of going to 12 mpix as "back in the MP race". These two cameras are clearly purchased fairly often based on reviews and street credibility, so its a fair bet that the extra megapixels in the updated do improve picture quality measurably.
Personally, I wonder if its not a back-illuminated CMOS instead of a CCD. That would quickly explain the megapixel jump and big jump in video capability.
After all, its not as if Canon can really make a one-off sensor for this segment, which is why Canon has been buying CCDs for this segment from Sony for a while.
Like I said before, these are pretty optimized designs, so evolutionary changes are all I would expect. On the S100, in-camera chromatic aberration correction could quickly yield some extra design freedom on the optics, though.
Makes you wonder about the market that the camera is being positioned to.
The G5, which was very firmly positioned towards the enthusiast segment (because DSLRs were
largely unaffordable then) sported a f/2 lens at the wide end. A faster lens (especially a zoom)
costs more to build, whereas the happy-snapper market is demanding greater zoom lengths,
regardless of the fact that there is a loss of image quality with super-zooms.
I wonder if the enthusiast compact camera market segment is large enough for Canon to
be really interested, or is it going to be left to the likes of Fuji (and Leica), and possibly the
M4/3 crowd.
I am personally quite happy with 10MP. I would prefer a bigger sensor, less noise and a brighter
lens as enhancements. Those are factors that would motivate me to buy a new camera, not a 2MP
bump in resolution (which is less than a 10% linear increase in resolution). Who knows, as well,
whether the lens is sharp enough to cope with more resolution...
Maybe I should wait for the G15 before upgrading my G11, and just quit whining.
G.
