http://numismaticnews.net/article/Wrong_date_on_Taylor_1_edge/ If it happened the way they are theorizing, could a 2010 Native American Dollar with a 2009 date have wound up in a roll of Zachary Taylors? Or could a Zachary Taylor with a 2010 date have wound up in a roll of 2009? Based on that theory would that add a "premium" to a roll of Zachary Taylor?
I would think it unlikely that those coins would end up in 2009 rolls of Zachary Taylor dollars, so I don't think it will add any premium. That's a really neat error. I think Ken is a little low on price. He could be right if enough are found, but I'm betting it's either unique, or there are only two or three. If that's the case, it will be many times the $10,000 estimate.
I don't think you would find a 2010 Taylor dollar in a 2009 roll of Taylors, but it might be possible to find a 2010 design NA dollar with a 2009 edge in a roll of 2009 Taylors. VERY unlikely but possible.