As mentioned by the Zend Developer Zone, PHP is still holding strong in the TIOBE Programming Community index n terms of how popular the language is. PHP comes in, once again, at number four on the list, bested by (in descending order) Java, C, and C++.
Most of the top languages on the index are staying around the same spot, but two languages - Visual Basic and Python - are nipping at the top four's heels. Things are getting pretty neck and neck for three languages - PHP, Basic, and C++. Their stats have been fluctuating just around each other, but not changing enough to make a difference in the listings.
You can check out the full listing on the TIOBE Software website (including a graph of each language in relation to the others).