I am using the latest version of PDT (version 1, released Sept 19).
I am using the PHP perspective:
When I right click on a directory in the Project Explorer and select "Open in New Window", a new window appears showing the contents of the selected folder in the Project Explorer. So far, so good. The question is how can I navigate back to the parent directory. This can be done when using the Navigator.
It gets worse. When closing down eclipse and when the window created with "open In New Window" is the last one closed, the next time you start up eclipse in the same workspace, it defaults to this state and then you cannot go back to see the projects using the explorer.