Andi Gutmans has posted some of his own thoughts about the recent Zend Server beta release over on his Blogspot blog:
As I alluded in my New Year’s post we’ve been very busy working on a new product line which today we are unveiling as Zend Server. Zend Server is not a Zend Core or Zend Platform derivative (although it uses a small amount of those components, mostly enhanced) rather it’s a new approach on how we want to develop, distribute, and service our production products.
He talks about some of Zend's reasoning behind the project such as the need they saw in the community for a good, easy to install full web stack that can be relied on to provide solid, dependable performance. The entire setup is free of dependencies making it idea for a "drop in" kind of package for those needing an environment on Windows, Linux or Mac OS X.
You can find out more information about this new Zend offering on this page on the Zend website.