One complaint we've heard often of ZF users is confusion over how acronyms
are represented in class names.
As an example, many suggest that "Zend_PDF" is more semantically correct
and easier to remember than "Zend_Pdf". On the other side of the coin,
many developers feel that our MixedCasing or Titlecasing of acronyms is
a simple, easily learned rule that makes typing easier.