Changing the Rules: Genesis 1-3

The straightforward, literal reading of Genesis 1-3 has proven to be a stubborn obstacle for those who embrace the "millions and billions of years ago" myth. To get around it, some evangelicals try to change the rules of interpretation in the first chapters of Genesis. After all, if the biblical creation account wasn't meant to be taken literally, then those who insist upon a literal, six-day creation aren't just wrong, they are doing violence to authorial intent.

Here's their simple (yet clever) tactic: they start by saying Genesis 1-11, especially the first three chapters, is Hebrew poetry. Some go further, saying it's allegory--the words aren't important; they're just a literary device God used to teach deeper, hidden truths. Liberals deny the supernatural elements altogether, claiming the biblical creation account is nothing but an elaborate myth. The point is, by changing authorial intent, they believe they can change the rules of interpretation too. In plain language, anything goes. Scripture becomes soft clay in the hands of the interpreter, to be molded according to his personal bias.

Is Genesis 1-3 poetry? Is it allegory? How would a poetic or allegorical view of the early chapters of Genesis harmonize with how the rest of Scripture treats the creation account, especially in the New Testament?

Listen to John's sermon excerpt, then reflect on the following scenario for the comment thread: Consider two different interpreters of the creation account—the first believes Genesis to be purely a historical account, but does not believe it. The second believes Genesis 1 and 2 are completely true, but were written as poetry or allegory. Which approach has more integrity, and why?