S100Mike - Indeed, for some, camera size is critical - but should that mean that they can't have all the basic functions?
As engineering-items - the S90-95-100 series seems to have no direct competitors at that quality-level, for the package-size.
But the low-price Canon A1200 does have a viewfinder - I've tried using my godson's one - "rather cute", at the $95.00 price here, for what it can actually do. For stills of anything moving, or video - while the viewfinder isn't exactly DSLR-style (how many on P&S cameras are, though?) - those things are far easier to do with the viewfinder, and get better results.
For an S100 at about 5 times the A1200's (Sydney) price - couldn't it have a somewhat better quality viewfinder, fitted-in as compactly as the A1200's? It would seem that Canon would sell a lot more of them if it had one....
It's interesting that you need 3 x power-packs for your S100 - if it had a 4 x AAs option - use Eneloops, and the viewfinder if it had one - and you'd likely get the 600 stills shots your 3 x power-packs get you - from 1 set... My older design SX10 gets 550-600 from 1 set of 4 Eneloops, stills only.
Here, S100 power-packs, NB-5L, are AUD$80.00 - so a couple of those as spares would put the AUD$469.00 S100 up to $629.00....
Even at our prices here - one can buy a Pentax K-R DSLR with 18-55mm kit lens, for $635.00.
And yes, that does have a viewfinder - and optionally can run on 4 x AAs... 
Just teasing - obviously a different sort of device! But - at the prices we pay here for "trendy" cameras like the S100 - it IS a comparison folk here tend to make.
Oh? AUD$80.00 (USD$86.09) for an NB-5L - when they're about $40.00 in the US?
See pic...
Regards, Dave.
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