On Friday night Michael Bane told me that BATFE visited the Taurus booth at SHOT Show and declared that the 28 gauge revolver was in fact a SBS (Short Barreled Shotgun), not a handgun.
Guns America removed a blog post about the pistol (H/T: TruthAboutGuns) and replaced it with the following text…
Editor Note: Taurus has removed this firearm from their booth and has elected to not make it at this time. The rifle version will be available through Rossi at some point.
Taurus USA imports their pistols from the Taurus factory in Brazil. If they were imported the sample 28 gauge SBS and specified in the US Customs / BATFE paperwork that is was a pistol, they could be in trouble.
I contacted the Taurus PR but I have not yet received a reply.
UPDATE: According to Taurus PR this information is apparently not correct.