I've read an article about facebook ads, statistics, and they weren't very positive , even for big box retailers. They described the way they had their advertising set up not current with today's trends, and that most people don't log into facebook when they want to shop online. The best strategy for any business is word of mouth, so when people see that their friends "like" a page on facebook, that would be a lot more effective, then any type of "banner" ad no matter how well the text was written or how well it was placed on the page. To facebook it doesn't matter they rake it billions of dollars annually from businesses willing to take the gamble and invent in their adds.