All experienced scholars, who favour Open Access, know that it is important to stay away from predatory publishers. For finding out by yourselves what a predatory publisher is, this is a recommended reading: http://wp.me/p280Ch-g5.
Jeffrey Beall monitors the scene of predatory OA publishers regularly and a recent update is a avilable here: http://scholarlyoa.com/publishers/.
Now my question is whether you actually use this list before publication to exclude certain potential or probable predators. Is this comb-out part of your academic publication process?