I don't get much comments, at least not these days, but for posts that do get many comments also have a interesting characteristic that they also get re-posted in many other websites. For example if X writes an article P which is very interesting, websites like Reddit and Digg and other people Y and Z will also post the same post. The problem is everyone will have a set of comments that are not in the same place.

My suggestion is to have a new method where along with the post you also have a traceback for comments.