If you’ve just installed Adobe CS3/4 you may be wondering why your Safari on OS X can’t display PDFs anymore.

It’s because Adobe mucked up the plugin which tells Safari to choose an application to view the PDF files.

To fix the problem go to:
/Library/Internet Plug-ins/

and delete the file:
AdobePDFViewer.plugin

Restart Safari and you will be looking at PDFs in a snap.