After scaling infrastructure and preparing IntenseDebate to deliver super-charged performance to additional traffic that is likely to come when WordPress starts, Intense Debate is back to public with a new WordPress plugin with following features:

• Comments made in IntenseDebate are automatically backed-up to WordPress, while your existing WordPress comments are automatically imported into IntenseDebate.
• Moderate and reply to IntenseDebate comments from your WordPress admin panel using custom moderation page.
• IntenseDebate outputs the standard WordPress comments enabling your comments to still be indexed by search engines that ignore JavaScript, while ensuring that visitors surfing with JavaScript disabled will be able to interact with comments made in IntenseDebate.
• trackbacks and pingbacks are all automatically synced to your IntenseDebate account.
• Profile Sync: Syncing your accounts enables auto-login so logging into WordPress automatically logs you into IntenseDebate.
• WordPress admin settings like closing and opening comments on a post, and even changing your post titles, are automatically recognized and reflected in your IntenseDebate settings.

More info: IntenseDebate