I've not seen SD400, but tested on SD500. Canon DIGIC II really plays a great deal. The noise is much lower than the previous IXUS S500 I had when I placed the taken pictures on my screen. I'm not sure about the sales price, but quite reasonable not too expensive. Try SD500 at your nearby dealer.
I am considering the SD400. I had purchased the Sony T33, but I find the image-quality to be rather "soft" and not as sharp as the Canon S500 that I used to have.
Does anybody have any user or editorial information on the SD400? I know it won't be released by Amazon for two more days. I heard that the LCD on the SD300 cracked often, and I was wondering if the SD400 had that same problem.

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