“From a security point of view, Gutmans noted that Magic Quotes,
which in the past has been considered to be a security concern,
will reach end-of-life in PHP 5.4.
In PHP 5.3, the most significant new feature was the
introduction of namespace support, which is a way to encapsulate
classes and other PHP items. The namespace support was a big change
for developers, but there likely isn’t going to be the same type of
big ticket item in the PHP 5.4 release.