Why are client libraries for web services such as Akismet, Amazon, Audioscrobbler, Delicious, Flickr, Nirvanix, Simpy, StrikeIron, and Yahoo! part of the Zend Framework standard library?
Zend Framework has been designed to solve the most common problems in web application development. Web services are a big part of today's web development environment. So much so that many of our users consume our web service clients for services such as Amazon ECS, Akismet, and ReCaptcha before adopting more infrastructure-oriented components such as Zend_Registry and Zend_Log. Because these web services play such an important role in today's web applications, we consider them 'first-class citizens' in ZF.