CoComment had a good amount of time to get out ahead, but now the new blog comment startups are coming out in force.

CoComment, you’ll remember, allowed users to track their comments across multiple sites and blogs via a bookmarklet, and (later) blog plugins. Disqus, from YCombinator-funded startup Big Head Labs, is taking on this market too: they’re set to launch a comment system with voting, threading and user profiles. The site isn’t yet live, but Fred Wilson’s blog is currently using Disqus in its comments. Meanwhile, Disqus also provides mini profiles per commenter, and an aggregated page (or “forum”) for comments on that blog, helping you to find the best ones. I wasn’t able to confirm how the comments are activated (code insertion or plugin), but Fred’s blog is on Typepad.

It’s an idea that has suddenly become popular again for no clear reason: IntenseDebate (covered here) does a similar thing, hosting all comments on their servers and potentially creating a problem if you ever decide to switch back to your own comment system. SezWho also has a CoComment-style system, with the addition of reputation ratings for commenters.

Which do you prefer? And are there any we missed?