I lifted this directly from the ‘help’ section of wordpress.
I really don’t get why people keep messing with a clock that works well enough.
We’ve recently updated our commenting system.
Now, if someone tries to comment with an email address that’s attached to a WordPress.com account, they’ll need to sign into WordPress.com before they can comment.
If commenters have forgotten their password they can request a reset:
Please don’t hesitate to contact our Happiness Engineers if you have any questions. We’re glad to help!
We discovered a bug that required some users to use an email address when commenting, even when the blog owner doesn’t require an email address, or might prevent logged-in users from commenting.
This bug has been fixed. We’re sorry for any inconvenience this might have caused.
We discovered another bug that prevented some users from commenting if they attempted to comment on a blog with a custom domain name and had third-party cookies disabled.
This bug has been fixed as well and we’re sorry for any inconvenience this might have caused.
WordPress.com and Gravatar.com accounts are the same thing. Accounts for each service work on the other. So if you’ve only ever used Gravatar, you can log into WordPress.com using your Gravatar account (and vice versa) to post using your registered email address.