Actually, it's only a fictitious web project the IBM Internet Technology Group team developed, but it's quite interesting that they used Drupal for the chosen platform to facilitate Using open source software to design, develop, and deploy a collaborative Web site:

Drupal is a relative youngster compared to other content management systems (CMSs). However, we got the impression the framework was well written, robust, very extensible, and seemed to have a thriving development community that was generating a lot of adoption and support....

... Drupal is known for scalability, or ease of growing a Web site from a small set of users to an enterprise level. The framework also has the ability to 'throttle' areas of the site that could cause potential problems during heavy traffic situations.

There is still an apparent learning curve to the "Drupal Way" of creating sites, but significantly less compared with other CMSs. The ability to use PHP to move freely between the business logic layer and the presentation layer (using the PHP template engine) was also very appealing.

They compare Drupal with some other popular CMS platforms, and then get into some detail. Check out this comparison chart, and what the IBM engineers have to say:

Drupal contains many built-in features and is easily extensible with a vibrant community supporting and adding to the portfolio of additional features. The basic features include:

• Friendly URLs using Apache's mod_rewrite capability
• Easily extensible using Drupal's module framework (The community has developed many useful modules that provide functions such as taxonomy display, jabber authentication, private messages, bookmarks, and so on.)
• A personalization environment for individualized content and presentation based on user preferences
• Role-based permission system to define access to the viewing and editing of content
• Content is fully indexed to support search
• Drupal is written on top of a database abstraction layer, so the framework can be easily extended to other database back ends
• Support for other content forms such as polls, threaded comments, and discussions and content syndication
• Separation of content from styling in a templating system that uses HTML, CSS, and PHP
• Administrative support for logging, analysis, and Web-based administration
• Online help

They then go on to list some of the ways they extended Drupal.

• Laura's blog
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