When Ebert tweeted that he was unaware of the term's pornographic connotation, Big Hollywood countered that he had referred to such a context in past movie reviews.Ha. It must have been "Pecker." I love that movie. Yeah. Here's Retracto the Correction Alpaca calling gotcha on Ebert — complete with "Pecker"-clip. Frankly, I can see how someone could have reviewed "Pecker" and even talked about the teabagging in "Pecker" — which is pretty silly — and not realize that the word had moved beyond that context into the general parlance and was implied by the term that is now used to mock tea partiers.
That movie also uses the expression "shopping for others." I remember that, but remembering that doesn't tell me that it's become a term for something people are really doing these days. [ADDED: I see that the link within that link now goes to the absence of a YouTube clip from the movie. It was a scene in which Pecker, a budding young photographer, and his friend go into a store and put embarrassing items in other people's shopping carts when they're not looking. Pecker then takes pictures of their reactions at the checkout counter.]
Anyway, I welcome Roger Ebert to the Tweet-o-sphere. It's great when an excellent, interesting writer takes to the 140-character art form. Follow him here. I am.