While it may be true that TSA agents need some discretionary authority to confiscate items at security checkpoints, this one seems to be pretty high on the common sense scale.
Photographers often carry an air-blowing device which consists of a rubber squeeze bulb and a plastic nozzle to remove dust from the very delicate sensors and lenses of digital cameras. Touching the sensor can ruin it, so there are no hard metal parts on the puffers, which are usually small enough to fit in the palm of the hand.
But Gizmodo reports that another blogger, who goes by the name of Gynocerous, had his puffer confiscated at a TSA checkpoint in the Newark airport because it "looks like a bomb" ... a cartoon bomb.
Maybe it was the name ... a "Giottos Rocket Blower" ... which made TSA take note of the item. You can see the device by following the FMI link and determine for yourself.