Currently the active, selected, project is displayed in the statusbar of the main screen.
However by convention most Windows applications add it in the program name in the Title/Caption bar of the main form.
This projectname is then revealed in tasklists and Areo Peek popups, which make it easier to spot.
Suggestion (minor): remove projectname from statusbar and add it to the program title/caption.
Example "Rapid PHP 2012 - MyOpenedProject"