PHP 7.0.0 comes with a new version of the Zend Engine, numerous improvements and new features such as

• Improved performance: PHP 7 is up to twice as fast as PHP 5.6
• Significantly reduced memory usage
• Abstract Syntax Tree
• Consistent 64-bit support
• Improved Exception hierarchy
• Many fatal errors converted to Exceptions
• Secure random number generator
• Removed old and unsupported SAPIs and extensions
• The null coalescing operator
• Return and Scalar Type Declarations
• Anonymous Classes
• Zero cost asserts

For source downloads of PHP 7.0.0 please visit the downloads page, Windows binaries can be found on windows.php.net/download/. The list of changes is recorded in the ChangeLog.

The migration guide is available in the PHP Manual. Please consult it for the detailed list of new features and backward incompatible changes.

The inconvenience of the release lateness in several time zones is caused by the need to ensure the compatibility with the latest OpenSSL 1.0.2e release. Thanks for the patience!

It is not just a next major PHP version being released today. The release being introduced is an outcome of the almost two years development journey. It is a very special accomplishment of the core team. And, it is a result of incredible efforts of many active community members. Indeed, it is not just a final release being brought out today, it is the rise of a new PHP generation with an enormous potential.

Source:

http://php.net/releases/7_0_0.php