In the wake of a series of high-profile hacks, Twitter has updated it's e-mail sending systems to help prevent phishing attacks from being successful. Known as DMARC, the new technology helps identify an e-mail as legitimate and allows e-mail providers to block e-mails that come from forged domains.
The technology is rather new and has been created to help fight e-mail phishing attacks. All four of the major e-mail providers--AOL, Gmail, Hotmail/Outlook, and Yahoo--have gotten on board with the new technology and are already rejecting e-mails coming from forged domains.
It will be interesting to see just how well this technology works to cut down on Twitter hacks. If you'd like a more technical explanation of the technology, you can find more information about the DMARC technology on their website.