For various reasons related to our WordPress trademark, we ask if you’re going to start a site about WordPress or related to it that you not use “WordPress” in the domain name. Try using “wp” instead, or another variation. We’re not lawyers, but very good ones tell us we have to do this to preserve our trademark. Also, many users have told us they find it confusing.
If you already have a domain with “WordPress” in it, redirecting it to the “wp” equivalent is fine, just as long as the main one users see and you promote doesn’t contain “WordPress” and in the long term you should consider transferring the old one to the Foundation.
“WordPress” in sub-domains is fine, like wordpress.example.com, we’re just concerned about top-level domains.
We’ve told this to anyone who has ever asked us, we just wanted to make it public so more people could be aware of this policy.
Other domains are using WordPress in them!
If they’re not WordPress.com, WordPress.net, WordPress.org, WordPress.tv, or WordPressFoundation.org, they’re not allowed, and you should contact the owner with a pointer to this page. We see this most frequently with spammy sites distributing plugins and themes with malware in them, which you probably don’t want to be associated with.