The account setup pages have several HTML errors exposed by the W3C Markup Validation Service. The worst is on line 169. A reference to the non-existent ID "user_password" causes the next field, email, to forget the email address submitted. This error bumps the attempt counter, thus giving the user only 3 actual attempts to setup an account.
The following link invokes the validator and lists the errors for / account/new: http://validator.w3.org/check?uri=https%3A%2F%2Ftwitter.com%2Faccount%2Fnew&charset=%28detect+automatically%29&doctype=Inline&group=0 -- Twitter developer documentation and resources: http://dev.twitter.com/doc API updates via Twitter: http://twitter.com/twitterapi Issues/Enhancements Tracker: http://code.google.com/p/twitter-api/issues/list Change your membership to this group: http://groups.google.com/group/twitter-development-talk?hl=en