What always stuns the hell out of me about these debates is how apparently intelligent, rational, logical people can fail to understand the difference between knowledge and belief.
I have a simple challenge to anyone who thinks that agnosticism is "wishy-washy" or "fence-sitting", or in any way an untenable position to hold.
Prove either that god exists, or that god does not exist. I don't care which.
If you can provide a water-tight logical proof, one way or the other, I will cease to describe myself as agnostic. However, if you cannot provide such a proof then you must admit that you are actually agnostic.
By agnostic I mean "lacking definite knowledge of whether or not a god exists", and by god I mean "an intelligent entity which caused the Universe to come into being".