My father teaches a college course using Alice. It's sort of a programming for non-computer-science majors class. I've sat down with him a couple of times and played with the program. I suspect that for someone who doesn't have any programming experience Alice is really fun (creating movies, making things move onscreen), but for someone with any experience its all just a hassle. Too many mouse clicks and drags are needed to get simple things done, and sometimes the natural-language style of the program isn't as natural-language as you want it to be.
But if it's a free program it can't hurt to try it out yourself.