Andi Gutmans (of Zend) has posted an update on the status of the Zend Framework for the month of May:
This [May 15th maintenance release] reinforces our commitment to high quality and we will continue to release periodic mini releases on an as needed basis.
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[...] Not only is the Zend Framework user base growing rapidly but we are also seeing a sharp rise in adoption of ZF in business-critical commercial applications.