[themes] Drupal features page needs better description of theme capabilities

[Kieran Lal]

http://drupal.org/features

Templating - Drupal's theme system separates content from  
presentation allowing you to control the look and feel of your Drupal  
site. Templates are created from standard HTML and PHP coding meaning  
that you don't have to learn a proprietary templating language.

Detailed information links to --> How to write themable modules:  
http://drupal.org/node/306

Blocks
Regions
Variables available in theme template
Additonal variables in theme template
Customizable templates
Customizing themes for node types, terms, sections, paths, and front  
page
Theme functions

What else should we describe?

Kieran