An interesting (perhaps) follow-up:
Neil deGrasse Tyson was interviewed in the January 2013 issue of Sky magazine. He was asked "What was around before the Big Bang?". He answered "We don't know. That's the answer. We have some strong ideas but they're not elevated to the level of theory yet. But one of them is that we might be one bubble of many bubbles in a multiverse. The multiverse would have been around before we were born in it, but that just pushes it farther back. Where'd the multiverse come from?..."
I don't think scientists talk enough about this logical dilemma. For instance, Stephen Hawking spoke at CalTech in April 2013. From what I can gather, he essentially said he favored the multiverse explanation of where the universe came from, but (as far as I can tell, I don't have the text) he did not go further and discuss where the multiverse came from.
FYI - The quote from Neil deGrasse Tyson is impossible to find online. I can post a scan (if allowed) from the physical magazine if anyone is interested.