Twitter has finally rolled out a feature users have been clamoring for for months: two-factor authentication. The update adds a layer of security that should help defend you (and any news organizations that haven't changed their passwords yet) from unauthorized log-in attempts.
You can enable the feature when it's available by heading to your Twitter settings page and checking the box that says "Require a verification code when I sign in." (It might not be available yet; Twitter seems to be rolling out the feature gradually.) The next time you log in, Twitter will ask you to provide a shortcode that it'll send you via text message.
To grant access to third-party apps, you'll need something akin to Google's application-specific password, a unique key that isn't sent to your phone but allows the apps to bypass the two-step system.
It should help prevent embarassments like the Associated Press seeing its Twitter account hacked.