So, apparently disqus rocks. When I’ve applied it to this site I could reach a substantial reduction in code size, since most of the code (especially public-facing code) was dealing with
- comment spam handling
- banning of commenters
- OpenID authentication
- comment formatting
and so on. All of these are a burden and disqus does all of these better than I ever could. However, if you have a homebrew blog system (as I do in case of Inkpot) you will not have a simple plugin provided to flush all of the existing comments to Disqus. However, you can use this gist as a template - all it takes is a little Builder and some lap-dancing to output namespaces properly.
Run this to a file and you will get a Wordpress export that you can import into Disqus. If you store emails properly all of the comments will be also wired into their respective accounts there, automatically.