Atheists Who Believe In God?

This post over at Get Religion got me thinking, and very confused. Apparently, in a recently released Pew Forum poll, twenty-one of those who call themselves atheists stated that they believe in God. Eight percent of atheists are absolutely certain God exists.

Now, I always thought of the word atheist as meaning what nearly any dictionary will tell you it means, something like “one who believes that there is no deity” (Merriam-Webster). I do think, as many people argue, that we should include in the definition the person who does not believe there is a deity, yet has not consciously chosen either agnosticism or actively to deny the existence of a deity. That said, it appears based on Wikipedia’s entry that the term is being used by at least some people somewhat more broadly, such that rejection of theism counts as atheism. That is, rejection of belief is treated is synonymous with disbelief (a logical fallacy; “I do not believe X is true” need not equate to “I believe X is false”). Apparently, some people are redefining the term so dramatically as to see belief in a singular God as compatible with rejection of belief in a god or gods.

I don’t understand. Anyone care to explain this to me? Are some people simply muddled? Maybe Steve Waldman at Beliefnet is right in saying, “Atheism has become a cultural designation, rather than a theological statement. Some are likely declaring themselves atheists as a statement of hostility to organized religion, rather than to God.” Thoughts?