I've tried it with a couple of small bowls and it has certainly speeded up the drying time. I've got a larger deeper one drying at the moment which I haven't put in the microwave and that has really elongated, should be interesting when I try to finish it.
I haven't tried microwaving wooden pan blanks, but I might give it a go, I got a beautiful block of spalted beech a couple of weeks ago which has developed a very bad (deep) split. So a mate has taken it to work to turn into pen blanks for me. I'll try it on those.