The value of Facebook as a marketing communications channel is now indisputable. Brands are beginning to increase their advertising investment in the platform, some as much as 10 times last year's spend. Additionally, companies are focusing more effort on engaging with their Facebook fan base through constant communication and highly interactive content. At the same time, many other brands are struggling not only with bringing their customer base into the Facebook ecosystem, but also with engaging those fans once they "like" the brand. Following are three main reasons why.