A colleague of mine, a designer, claimed in a recent conversation that she never visits microstock sites (the name Istockphoto didn't actually ring any bell). According to her, all the pictures and graphics her company needs is usually taken from Getty or Alamy. The reason: not enough variety in micro.
Maybe I should point out that what they do (as far as I know) are pretty specific projects for the Dutch market, concerning antiques, curiosa etc.
Still, it's been on my mind lately; do you have experience with the designers' side of stock? Is it possible to judge if the big agencies (which apparently don't mind the price that much) are moving toward microstock or staying with macro?
In any case, maybe it's a good moment to start shooting more "out of the box", niche images. Which reminds me, my bro used to collect snails