The Tails GNU/Linux development team announced release of Tails 1.5.1, the latest update of Debian based GNU/Linux distribution featuring tools that ensure your privacy and anonymity while surfing internet.
Tails 1.5.1 is a critical release or in another words it is an emergency release triggered by release of Mozilla Firefox with some critical security fixes. Tails 1.5.1 includes Tor Browser 5.0.2 which is anonymous and secure browsing tool kit, based on Mozilla Firefox ESR 38.2.1.
For more information, read official release announcement