Not that this means I agree that you as a developer should do this, just that I understand. There are lots of hidden issues too - your service now has added an

Not that this means I agree that you as a developer should do this, just that I understand. There are lots of hidden issues too - your service now has added another third-party dependency that could kill you if they decided to break in some way that you couldn't reverse from. Facebook now has all of your user/traffic numbers which they can use against you if they ever decide to compete with you on any front. In the future, advertisers can potentially reach users you've pre-targeted without paying you and instead paying facebook. The list goes on. It's putting a lot of trust in your relationship with facebook.