Many blogs and even news sites have replaced custom comments systems with Facebook comments. This obviously comes with advantages:

Many users are probably already logged in, or have a login ready at hand.
No registration process.
If a user posts a comment this will show up in their stream, hopefully advertising your site to their Friends.
It's a paradigm people are already familiar with.
In theory reduced spam.

But is it all upsides? Very little ever is. Even some of the above advantages are double edged swords with possible downsides:

If a user doesn't have and doesn't want a Facebook account, they can't comment. Similarly, if Facebook closes someone's account for any reason, they can't comment on your site.
There is a registration process, it's Facebook's. It's out of your control. Facebook's registration process may very well be more involved than is necessary for a simple comment system. Similarly, if your site has any other membership requirements (e.g. your site is commercial, and you need customers to register in order to place purchases), then you already have a registration process you should probably be putting to use.
Some people don't want their stream spammed with notices every time they comment on an article or blog.
While it's a paradigm users are familiar with, it lacks many features that more advanced comment systems have; such as concepts of threads. And again, you have no control over it.
Additionally, there's very little chance the Facebook comment system is going to look like it belongs on your site. Unless you've designed around them, they're probably going to look tagged on and out of place.
While spam will be less than an open registration process, there are literally millions (estimates of up to 80 million) fake Facebook accounts out there, which are mostly used for spamming.

So then the question is; are Facebook comments right for your site? If you want a quick, fairly simple comment system that most users are already going to be able to use with no hassle, maybe. But make sure you consider the possible downsides. There's still plenty of reasons to have a custom comment system; or to use the one that comes with the web platform you're basing your site around (such as the WordPress platform.)

If your site already has a registration process of some kind, as mentioned, you should probably be using that for the comment system as well. It will help get people who are interested in commenting to sign up as customers, and help customers feel more involved in the rest of your site than if there's a separate registration/identity being used for your comments.

Lastly, it's important to consider whether you want to have comments or not. Any comment system is going to be targetted by spammers, and that's something you're going to have to deal with. Additionally, you want to make sure that you monitor them so that when people try to engage you, you respond if appropriate. Or readers will quickly learn you aren't interested or invested in the comments, and move on. It's better to have none in that case, than a system that is neglected.

With regards to this blog itself, we currently do not have a comment system but will be creating a Forum in the Hosting.com Community Forums to discuss blog posts. And of course, customers can always contact us via the Hosting.com Suggestion Box with any comments, feedback or suggestions.

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