Oneof the big problem in the debates is the reduction of options to the two common ones: take Genesis literally, and reject all science that says anything to the contrary, OR, take whatever science says as infallible fact, and just realize that the Bible was mistaken in science fact, yet we can still glean good, moral principles out of it. And yes, the bible is a morality tale, not a historical record.
The problem is, to people who take it seriously, if it was wrong about science and history, then its credibility is questionable for everything else.
Of course, this is the view on the far "scientific" extreme: that it was just an ancient fairytale book, whose purpose was at best to fabricate a basis for morality, and at worse, just a tool to control others through fear with unprovable claims.
Then there is a more moderate view that says the Bible was not in error, just allegoric. But then again, much of it, which was written in absolute terms, would lose real meaning, and anyone could interpret it in any way (Which is what goes on in the religious world anyway!) If it is just something to glean moral principles out of, then people will be selective about it, and it will again lose any real significance.
(I believe it was somewhere on this board that someone posted a link to the Youtube video of Bill Maher doing a sketch of Jesus siding with the Prop 8 opponents on the basis that the proponents were being selective in that they no longer obeyed several Old Testament rules such as the kosher laws. However, those were officially declared to be nailed to the Cross; while homosexuality was still spoken negatively of in the New Testament. Though there was a great point that the fervor with which people oppose and condemn other people's morality is based on the OT concept of a theocratic nation, which also ended with the OT, yet they try to hold on to).
I myself have always struggled with how Genesis could be true, or how much could be symbolic, or based on the limited perspective of the writer and original readers. The same thing actually happens on the other end of the book, with Revelation. Right there, I have recently found that most of the prophecies evangelical Christians claim are future were actually fulfilled with the destruction of the Temple in AD70. We were all thrown off by statements such as "the whole earth" being evangelized, (which has not happened yet), but then ignored or bent/stretched much clearer "time indicators", such as the end coming "shortly", and even before "some of you standing here...taste death", as Christ told his audience. But a close study of OT language will show that "earth" was used to represent the local area, or Israel. "World" was actually "age". This changes everything. So we got hung up on "space", which was actually more relative in definition, but ignored time, which was more absolute, as man can only live but so long.
So likewise, Genesis would probably also be better explained through this grammatical lense. Now, we would have a better justification for a local flood. Either that, or the fundamentalists need to conclude that the laws of the universe were vastly different back then, if they want their rigid literalism. There's actually a clause in string theory that says that the laws of the universe can change instantly (though the results would generally be cataclysmic as matter breaks apart of reforms. But that would be an idea).
But they instead insist the laws were the same; God was just interfering with them, even though he no longer seems to do this (and many of these old-liners are sternly against modern charismaticism which claims God is always intervening supernaturally today).
So that would give us a biblical framework for less than literal interpretations. But too often, the approach of non literalness is just to slap a generic "allegoric interpretation" label on the issue, without any such framework, and it just looks like a cheap attempt to get around the passages that don't make sense to us. so the literalists reject this and keep insisting the literal approach is the only "safe" one. I had fallen into this for years.
Makes sense, as the religious conservatives ironically sided with a social-Darwinistic approach to politics (like in their defenses of laissez-faire capitalism).