Good point. If you post virtually anything online in front of an audience of any size, someone is going to vehemently or ignorantly disagree ("Puppies are cute;" "NO THEY'RE NOT"). I wrote about the problem here: http://jseliger.wordpress.com/2009/12/30/trolls-comments-and... but have noticed it elsewhere, too, and the larger the size of the audience, the more likely it is to have some number of vocal and ignorant members.