Well, PHP5 already has an __autoload function (http://us.php.net/__autoload) built-in. Namespaces can be complimented with autoloading functionality. The purpose of a namespace is to encapsulate functionality to further differentiate and relate those items, while autoloading simply examines files within the include_path to remove the need to call “require” or “include”. Namespaces aren’t meant to resolve include problems, although they can for some.

Personally, I hope PHP’s implementation of namespaces eventually becomes more like C#, with more autoload features built in.

For people that don’t know it, it works somewhat in the following way:
The classname Zend_Db_Table resolves to %include_dir%\Zend\Db\Table.php and returns an object of the Zend_Db_Table present in that file.

Don’t you find that a much more elegant way to resolve including problems? (For the Zend Framework that is)