From Facebook Developer Wiki

Can I use multiple comments boxes on a webpage?

Like under every blogpost on a blog...

AFAIK only one application script can be loaded at time and that means that comments are shared for every comment box on the page.

Thanks! VM

Sure. Just add an fb:comments_(XFBML) tag wherever you want a Comments Box to appear, and provide each one with its own XID. You need to load the JavaScript only once. Pete -- 563683308 12:28, 2 November 2009 (PST)