It depends on what you want to use it for. DISQUS seem to be wanting to cater to the long tail of blogs, JSKit/Echo is looking to super-serve "pro publishers"

It depends on what you want to use it for. DISQUS seem to be wanting to cater to the long tail of blogs, JSKit/Echo is looking to super-serve "pro publishers" (they power comments on a lot of news websites, etc) I like what Echo is doing but if it is just for a small blog you might find it overkill, plus I believe it isn't free. However, the feature set is interesting. As it happens, I don't use either on my blog. I don't see much value add in the end.