I've heard of people raving about the Image Stablizer function of Canon lenses, but others also say it's overrated.
My question is, before the IS arrived people still took great pictures, so what does the IS do that other previous lenses didn't?
Because when I take pictures w/o a tripod and just a regular lens, the pics don't come out fuzzy or anything. How much "stabilization value" does the IS really add?

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