Unlikely, the chip would likely only transmit data to the language section of the brain, meaning the only thing the chip may access is how you read and translate sounds, writing and other things into something you understand. Possibly it may interact with the decision making, as in what the user wants to do next in 'browser' mode. I still reckon its speech recognition or even input based on holo-boards and such in order to avoid the scenario you are placing up.
I severely doubt the entire populace, nay the designers would let the chip be open to such a devastating attack.
However, a good EMP to the brain 'may' damage your brain through the chip, as shown in the film Surrogates.
I strongly doubt your scenario would happen Cam.
EDIT: @Dragonslayer - Very likely, look at HDTV buzz words. Capitalism against logic.