How many of you use external commenting systems like Facebook Comments, Disqus or Intense Debate?

I'm tempted to use Facebook comments on my new music site simply because it would help increase my Facebook presence, and because it gives more meaning to those comments (which would otherwise probably remain like lone islands). Other advantage is the fact that most people are already logged in to Facebook so they can start commenting right away, hassle free. Disqus and Intense Debate have less of those kinds of advantages, though Disqus seems quite popular, but look much better than Facebook Comments.

The disadvantage may be that you're kinda locked into the third party provider for your comments, and might have issues if you decide to switch to another system or self-hosted comments. In case of Facebook people might be a little hesitant to comment if they think their comment would immediately appear on their wall..

What do you think?