Originally Posted by
Jon Ruyle
Basically, the macro lens will just allow you to get closer. If this is what you want to do, then yes, the difference between the macro (either IS or non-IS) is like night and day compared to your 70-200 f/2.8 IS (which I also use for closeups of flowers and butterflies).
But if you're planning to take pictures hand held using available light then no question- get the IS. I should add that taking macro pictures this way, even with IS, is a very tricky business, because there just never seems to be enough light.