"2. Assuming the bible to be the word of god, then either (a) god intended the bible, as his word, to contain a mention of unicorns,"
Jamie, this still isn't a problem, unless you consider the BIble to be an exhaustive encyclopeia of zoology, which no one does. If, on the other hand, the Bible purports to be a bit of communication from God to humanity in form of history, parable, prophecy, poem, poetry, wisdom, and maybe some other literary forms, then I don't see why it's embarassing to Christianity at all if God did mention unicorns in a clearly poetic passage.
"No, but I am under the impression that the Christian concept of god is inherently self-contradictory, and the idea of the bible being "the word of god" is a good example of this."
You're probably under this impression because you have an atheist's impression of God, not a Biblical impression of God.
"If things are unclear, that's either God's fault, or it isn't. If it isn't, then God as he is commonly presented probably doesn't exist."
This is a very curious argument indeed. What about God, "as he is commonly presented", does not leave room for human error? Honest, non-rhetorical question here, as you and I likely have a pretty different idea of the common presentation of God.