Sorry I just wanted to rephrase that I am sorry, you didn't say there wasn't any IDE's for PHP but honestly Netbeans is (I think personally) one of the best IDE's out there. Though I have never used Eclipse.

There is the Zend Studio Client which can plug into a Zend Server (an extension to a HTTP server) that can profile performance of your PHP applications on the web and show you codes which are taking longer to process through so you can spot problems much quicker.

But to use some of Zend Servers more Advanced Features (all of them actually) you have to pay for a licence. Zend Client is pretty much like Visual Studio really (least I remember it being called that years ago in 2005/06).