I first heard about his on talk radio this morning as I was driving to the courthouse. When I got back to my office this afternoon I did a search on Yahoo News, tracing the story back to CNSNews.com. Nobody else seems to have covered the story.
The ATF, with the cooperation of local and State police, descended on a gun show en masse; the article states that nearly 500 police participated (I'm a little skeptical at that number). They parked cars in obvious places and seem to have made very sure that everyone knew they were there. One guy who was there to legally sell a couple firearms was rousted and held for having a suspended driving license.
The worst is that the ATF took information which could only be legally used for the computer check and sent officers to the houses of people who were buying firearms to question people about the purchaser: "Gee, did you know your husband was going to a gun show today? Do you have his cell phone number? Did you know he was buying a gun?"