Great article in which Ron Rosenbaum flies from Huxley to James Brown and offers a compelling argument for non-agnostics:
Why has agnosticism fallen out of favor? New Atheism offers the glamour of fraudulent rebelliousness, while agnosticism has only the less eye-catching attractions of humility. The willingness to say "I don't know" is less attention-getting than "I know, I know. I know it all."