If you haven't decided on anything yet, also take a look at the Panasonic LX3 P&S.
Advantages over G11/S90:
- F2.0 to F2.8 lens is faster than either canon at the same zoom setting.
- Wider lens starts at 24mm (both canon's start at 28mm). Go UWA 18mm with a pana brand converter that doesn't vignette!
- Smaller than the G11 overall, but a bit "thicker" than the S90 due to lens not retracting 100%
- Faster burst rate...2.5FPS is halfway decent
- adjustable aspect ratio switch. (I hate that canon's only record 3x4 and I have to remember to not shoot so tight at the top/bottom of frame to allow sapce for cropping when printing 4x6's...the most common prints for our vacation albums).
- The LX3 shoots the same 10mp at 3:4, 2:3, and 16:9 ratios with said switch. (on canon's you just have to crop off top/bottom on computer editing)
Disadvantages over G11/90
- less zoom range. LX3 only goes to 60mm...MAJOR ISSUE
- Doesn't have the cool "around lens" control ring as S90
- doesn't have viewfinder like G11 (why LX3 & S90 are both smaller)
- uses oddball panasonic hotshoe flash (P&S is small/pocket size..defeats purpose anyway)
But otherwise, they are very very comparable. Just about same image quality, all three shoot raw files supported by most converter programs.
If you are "wide angle addict", the LX3 is the better choice.
If your a TELE shooter, stick to the G11
if you want the absolute smallest pocket camera: S90
I had a Canon G9 back in 2008 for the summer to use for around the house, kids stuff, day vacations. It was good for that, but at the time I was spoiled with pro DSLR image quality and HATED the noise at 800-1600 ISO. I felt the lens wasn't wide enough all the time when shooting in the house (the G9 was 35mm-200mm). When shooting raw it was "one shot only" and took what seemed like forever to be able to take a second pic, not optimal with the way kids hold still. Minor grumble was it was just little too big for real pocket size, focus was slow, DOF was too great, and the viewfinder was WAY inaccurate defeating it's purpose. So I sold it only a couple months after buying it. <---in retrospect, I was expecting far too much from a P&S. There is no way the IQ and speed will be even close comparing a sensor that's about 1/8 the size as dslr.
Today actually, I just bought the LX3 (used on ebay $372 shipped). I'm a wide angle addict. It will be nice as well to shoot 4x6 aspect ratio again just like Im used to with DSLR's. I can't tell you how many pics were messed out of the G9 when printed 4x6's because I shot it too tight.
Hopefully it will be just a little better than the G9's P*S experience in most of my complaint areas that I will be able to convince myself that the image quality lost to my DSLR (D90 is what I use for vacations/kid stuff) will be made up for in portability. I'm kind of tired of chasing my two boys around WDW with a big DSLR swinging from my neck the whole time for what 95% of the time gets used for a P&S will suffice. Need to keep reminding myself that the portability is #1 thing.