1- A surprised or sarcastic, but acknowledging, response to a statement of intelligence from a usually ill-informed or negligible source.

2- A phrase uttered when someone makes a statement that is completely unnecessary, painfully obvious, or both.

Adapted from The Muffin Joke. As seen in the example, which definition is used depends on the respondent's perspective of the original comment.
1: Parent: "Halo: Reach was completely over-hyped."

Gamer Child: "Holy shit, a talking muffin!"

2: Parent: "Halo: Reach was completely over-hyped."

Gamer Child: "Holy shit, a talking muffin."
by TwiztedMessiah September 22, 2010
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