NetTuts.com has posted their own "what you must know" about the recently released (major) upgrade to the PHP language - PHP 5.4.

PHP 5.4 is here; the next major step forward since version 5.3 – keeping PHP 6 (full Unicode support) on hold for now. The latest enhancements significantly improve its elegance, while removing deprecated functionality, resulting in a dramatic optimization of the runtime (up to 20% more speed and memory usage reduction).

They hit all of the highlights:

• Traits
• Built-in CLI Web-Server
• Shorter Array Syntax
• Array Dereferencing
• $this In Anonymous Functions
• <?= is Always On
• Binary Number Representation
• Callable Typehint
• Initialized High Precision Timer

Code examples are provided where relevant.