Robert Heinlein was extremely progressive for science fiction at the time, but I don't think particularly progressive more generally. And that's more because of the weirdness of SF than anything else. I mean, I think Heinlein's political views in general are confusing and not easy to trace, and in a lot of ways probably weren't entirely clear in his own mind, and so I'm not attacking him or saying that he was a terrible person. But I don't think that he was hugely ahead of his time either.

I definitely agree that he's worth reading, though. At least his early work is usually pretty good. Moon Is A Harsh Mistress is a really good novel, and he has some great short stories too ("-All You Zombies-" is great fun).