How #newtwitter uses shbangs (#!) to let Google crawl AJAX content

If you're a Twitter user, logged-in, and have Javascript, you'll be able to see my profile here:

However, Googlebot will recognize that as a URL in the new format, and will instead request this URL:

Sensibly, Twitter want to maintain backward compatibility (and not have their indexed URLs look like junk) so they 301 redirect that URL to:

(And if you're a logged-in Twitter user, that last URL will actually redirect you back to the first one.), dependable as usual.