Php 5.4 is now available and is an installable option under cpanels easy to use easy apache.

So what should you be aware of in php 5.4?

Memory and Performance Improvements
Some early tests have shown that Zend Framework runs 21% faster and uses 23% less memory under 5.4, and that Drupal uses 50% less memory and runs about 7% faster. Some of the main features upgraded and changed can be found listed here:

http://www.oracle.com/technetwork/articles/dsl/lerdorf-php54-1564639.html

http://www.php.net/manual/en/migration54.new-features.php

What you should consider before upgrading to any version changes in php is how it differs from your current version. From php 5.3 to php 5.4 the main things to consider before making the change is that magic_quotes and register_globals have been completely removed in PHP 5.4 – so if your site relies on these aspects then you’ll need to re-write the site if you wish to move onto php 5.4.

The main list can be found here:

http://www.php.net/manual/en/migration54.incompatible.php

If you’re going for a major jump – 5.1 to 5.4 – you can see a very good list here:

http://www.php.net/manual/en/migration54.changes.php

Happy Upgrading!