The problem I have with all these drop-in-systems is that the comments belong to the system in use. I want to be the comments part of my site because most off them add value to the articles. There should be at least an option to export all comments into a machine-readable format so that I could take comments with me when I want to change the comment system.
So I know for a fact that disqus can export into XML, not sure about livefyre, but... you probably know how I feel about them after the article haha