The new Whatsapp update (version 2.12.413) on Android, brings Facebook account integration along with an option to enable encryption. While the Facebook integration would be available in the account setting options, there's also a hidden security setting that provides users with the option to enable encryption. Only rooted Android phones will be able to take advantage of the encryption features though.
Facebook has been adding features to WhatsApp ever since it acquired the instant messaging service. How users would benefit from Facebook account integration on WhatsApp though, is unclear at the moment. A screenshot taken by Android Developer Javier Santos, shows that the option appears in WhatsApp's Account settings and it will be optional for the Whatsapp users to share their account information with Facebook.
The 2014 partnership between Whatsapp and Open Whisper Systems helped the messaging service to develop better encryption systems by scrambling messages with a cryptographic key for better user privacy and security service. In a privacy security rating conducted by the Electronic Frontier Foundation (EFF), Whatsapp was rated poorly at 2 out of 7. This new update might bring favorable ratings for Whatsapp on the privacy security rating.