On the Zend Developer Zone there's a new post from Matthew Weier O'Phinney asking a question of all of the Zend Framework users out there - which do you prefer - ACRONYM or MixedCasing for how acronyms are presented 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. For ZF2, we started converting code to use each acronym's proper casing. However, we're not done yet, and there are good arguments on both sides of the debate.
They've set up a survey on the topic and encourage as many people as have opinions to go and cast their vote. The survey will close in about a week, so be sure and make your thoughts heard on the matter before then!