This is not a post against Facebook pages but more about making a careful decision to use them. The benefits of using a Facebook page is obvious which might be why we are all so quick to jump on board but we should question why we should not use them.
Are Facebook pages replacing web sites
I have seen this popping up all over the place.
"Are Facebook pages replacing web sites?"
I definitely don't think Facebook pages could or ever replace a web site. A website and Facebook page perform two different roles which make a good combination in distributing content to your audience. I think it is important to point out that a website is completely your own where as Facebook Pages are not owned by a company, they belong to Facebook. If Facebook wants to change the terms, interface or interaction they can even if a business wants their page to stay as it is. Content posted onto Facebook also belongs to them which is stated in their terms. There are many users at work that are not allowed access to Facebook making it less efficient to post exclusive content on Facebook.
Reasons not to have a Facebook page
It is possible that some Facebook users don't ever see your page since you can like a page without ever going on it. Also a user may land on it and like it but never return. By liking a page you are essentially signing up to a feed, giving no real reason to return to the page. Attempting to make your page unique might be unnecessary work. Even if the users do land on your page it is difficult to create a unique identity because all the pages are very similar in structure, even though you can customise it by adding a logo and modifying certain tabs.
Its also worth pointing out that not every person wants information from companies in their news feed. They want to keep their Facebook personal and rather search or follow an RSS feed of your information.
Since there is a reasonable expectation that users don't return to a page you rely on reaching them through their feed. An issue here is Facebook have a complex algorithm to place content in the feed. Even though I don't know the exact workings of the algorithm it is fair to say that part of it will be based on the number of likes and comments it gets, i.e. the greater the number of likes and comments the higher up it will be. There is every possibility that your content could be placed near the bottom and never actually be seen or clicked on.
Offering exclusive content is a great incentive to entice users onto your page but then this is increasing workload. Users will get annoyed and bored if you just post links without trying to be engaging, it would almost seem like a bot is posting links. Having promotional competitions just to get users to interact with your page seems like too much effort, surely time better spent finding a way to use the actual site. If you just want to post links short and sweet summaries, you are probably better off with Twitter.
There is a possibility that you will receive negative feed back which could spread like wild fire and potentially ruin your company's reputation extremely quick. An example would be Nestle.
No SEO value in pages as they are all "no-follow" links.
Major brands like Starbucks are using Facebook pages and they get a huge amount of likes but these likes have only come from their current reputation. They have already put a large effort into branding, marketing and getting them to enjoy there product well before they created a Facebook page. Trying to create a massive like list of fans is great but might be a missed opportunity to develop a powerful mailing list. Is a message to a user's Facebook any more powerful than sending it direct to their email? Plus with email you can control and style the email with HTML, Facebook messages are just plain text.
There are plenty of reasons here to not replace your site with just a Facebook page and considering if they are worth while. From my point of view a Facebook page is nice to have and can generate more traffic to your site, if used properly, but not really required to improve your site or brand. I think there is move value trying to interact with users more directly like email or comments on a site rather than through an intermediary.