Let's step back an analyze this issue of a literal Gen 1 for a second.
Gen 1 says, at face value, that God made various stuff in 6 days (with different things appearing during different days).
Now, if we examine His Creation, we find that, for all intents and purposes, God did not create as per a literal, "face value" reading of Gen 1.
Which presents a dilemma. Now, there are a few possible scenarios to resolve this dilemma:
A) The evidence we find in His Creation is false;
B) The people examining this evidence are making false conclusions about it;
C) The author of Gen 1 misinterpreted what God said;
D) The author of Gen 1 is lying;
E) God is lying;
F) God does not exist;
G) Gen 1 is not meant to be taken literally.
Now, each of these scenarios carries certain consequences:
If it's A, then clearly we cannot trust anything we find in His Creation, and this also begs the question of why such evidence is false in the first place.
If it's B, then the implications are that a vast majority of the world's scientists are either incompetent or part of a vast conspiracy of some sort.
C through F have all sorts of theological implications, calling into question the very basis of Christian theology.
G has theological implications, as well, but not nearly to the extent as C thru F.
Now, my own take would rest with G for three reasons.
One, scenarios A and B require me to adopt a stance of paranoia that I just don't see any reason to adopt. Basically, I have yet to see any evidence that His Creation is full of lies, or that the vast majority of scientists are incompetent or part of a conspiracy.
Two, taking into account the target audience the Bible was written for and is still written for. Considering the average scientific knowledge of your medieval peasant, it's not surprising Gen 1 is light on details. Furthermore, I believe it's the fundamental message that is important (i.e. God made everything), and the ability to convey and pass on that message in a least obtrusive way as possible. Trying to imagine a preacher explaining quantum singularities or genetic mutation to a bunch of peasants and, well, I can see why Gen 1 is worded the way it is.