Check out highlights from The Big Bang Theory Season 6 in this video. It debuted at Comic-Con 2013.
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The Big Bang Theory Season 6 Quotes

Leonard: Sometimes change is good. You were worried about Zachary Quinto being the new Spock, but you ended up liking him.
Sheldon: Leonard, please, every time the topic of change comes up you throw Zachary Quinto in my face. I'm upset the mailman has a new haircut -- Zachary Quinto. I'm upset daylight savings time started -- Zachary Quinto. I'm upset daylight savings time ended -- Zachary Quinto. I'm saying this for the last time. Zachary Quinto was a weird, wonderful, unrepeatable event, so stop using him against me.

Raj: Okay, here's another one: if a zombie bites a vampire, and the vampire bites a human, does the human become a vampire or a zombie? Or, a zompire?