.Just a few notes from an observer here...
1. Just as there are people on the fringes of Christianity who don't speak for all Christians, I think we can presume that there are people who are atheists who don't speak for all atheists. Nearly every time I hear of someone who had professed to be a Christian who commits some heinous, wrong or otherwise offensive act, all other Christians tend to line up to say, "Well, he/she isn't a real Christian."
I'm an atheist, and what I saw in Penn & Teller's bit was two atheists at a roast where patrons were clearly told, "There will be offensive things here," doing something for another atheist, who was the subject of the event.
I kind of think it's a little ridiculous to go into such an event, knowing full well of the caveat, and then say, "Well, I knew it was going to be offensive, but not that offensive." In for a dime, in for a dollar.
2. I think people aren't giving P&T credit for the fact that they are professionals. Opining that they might do something like they did at the roast for the Super Bowl halftime show is simply stirring the pot for no good reason. One was a private roast (that you had to be a member of a select group to attend), the other a publicly televised event.
3. If Andre Kole can travel the country with a magic show and tell children to believe in a God, why can't Penn Jillette tell a roomful of young magicians not to? Atheists have their beliefs impugned and condescended to every day, and one man speaking his mind is "offensive?" As for the roast event being designed to "advance the cause of atheism or rational thought," I hardly think that was the idea. I think the idea was to crack up the guest of honor. From what I hear, they succeeded.
4. The leader of the Catholic League was also the guy who announced protests against the movie "Dogma" before it had even been released, much less before anyone actually saw it. He might be trying to affect Penn & Teller's future careers, but I highly doubt that he'll have any effect. As long as they're funny, and bring in the crowds at the Rio, I think they'll have a long and successful career. It's not like they're touring through the Bible Belt any more (and they regularly got poor reviews down there -- go figure).
5. As for the P&T Showtime series, it may stink. It may be funny as hell. But they're trying to do something that is hard, and different (kind of like being creative and new in stage magic, something with which they've already had a rather successful track record), and not a lot of people like having their beliefs challenged, especially credulous TV reviewers.
Showtime doesn't need the kind of audiences for the show that regular TV does, and they can walk the edge. They already run "Queer As Folk," and I'm sure there's no shortage of fundamentalists who'd like to see that off the air as well.
And besides, career-wise, P&T have survived "Penn and Teller Get Killed," so I think they'll do just fine.