Another theory is the â€œS100″ rumors weâ€™re hearing are actually for a G13 and the â€œSâ€ series isnâ€™t getting an upgrade.
I think not.
If the rumor about the S100 is true - 12 Mpixel bump and no "G13" announcement, I think Canon's strategy is pretty clear.
The "S100" is probably real - it's the best competitor in the really-tiny pocketable category, and a major change like a larger sensor would not be an improvement - it would either end up bigger or with worse optics, so the S95 series will continue with minor tweaks.
But the "G13" absence, together with Nikon's soon-to-be-announced EVIL with a 2.7x crop sensor, is telling.
As far as I know, Nikon doesn't make sensors - they buy them from Sony, same place that Canon buys their small sensors for the PowerShots. So probably Sony (or, just possibly, Fuji) is making Nikon's 2.7x sensor - either way, surely they offered it to Canon too.
So, I'll predict that the G12 replacement will use the same 2.7x crop sensor used the Nikon EVIL. That means a total redesign, which explains why it won't be ready at the same time as the "S100".
Personally, I think that's a great decision on Canon's part, provided they do it right.
The larger sensor will be very welcome for less noise at high ISO. And I'd _love_ if they could make it focus faster - that's my main complaint with my G11 (more so than the noise). I hope it's not any bigger than the G12, which is already at the upper limit of size for me. And I really hope they keep the flippy screen - I won't buy it without one (I'd sooner buy a G12).
But an interchangeable lens on a camera in this size class really isn't important to me. I see the G-series cameras as high-quality but very portable cameras to be taken along when you're _not_ primarily doing photography If I need interchangeable lenses, I'm primarily doing photography, and will drag along my 60D and lenses (and tripod) for that.