Sam Harris got a lot of grief on our Churchland episode. Whatever the difficulties that Churchland (and allegedly Hume) may have with the is/ought distinction, Harris provides a much easier target for this kind of criticism.
Here's Harris specifically responding (starting around 1:40) to the is/ought distinction: "a firewall between facts and values in our discourse:"
He doesn't explain what's wrong with the distinction, but just says that it's had terrible effects: encouraging superstition and making science into something inhuman and amoral.
Around 4:30, he gives something like Churchland's response (and incidentally, she shows up at 5:15 as an audience member, and he refers to her near 8:40): we are social beings, i.e. it is a fact that most of us want to help others. At 5:50, he describes something like the pluralism Churchland advocated, using an analogy of food: there's not just one palatable type of food, but there's an objective distinction between food and poison. Does a social practice make for happier, flourishing individuals? No? Then it's bad.
Toward the end of the clip, and into part 2, he defends consequentialism, and his breed of it against utilitarianism (following much what Churchland says in her book on this topic). If anything, his emphasis on moral realism is much stronger than Churchland's (as I commented on the show, I think her main influence Hume presages Nietzsche in important ways).
Not until 4:00 in the 2nd clip does Harris actually bring up neuroscience, only to quickly drop it. He then attacks what seems to me a straw man: the view that the diversity of moral opinions means that they can't be in any way objective. At around 8 minutes, he brings up scientism but doesn't respond to the charge. His concluding remarks sound much like those of Churchland: moral reasoning involves ineliminable complexity, but we still have to navigate our way through it as best we can.
P.S. I was on vacation for a while and then replacing my PC, so we're a bit behind on the episode editing; it'll likely be at least a week still until the feminism episode goes up, but hopefully the existence of God episode (which has already been recorded) will come up within a week or two after that.