I just found out today that the folks over at Jcx. Software Corp have created a development environment called VS.Php that enables PHP Development from within Visual Studio 2008. Now PHP developers can take advantage of all the power of Visual Studio 2005 or 2008 including syntax highlighting, intellisense, debugging, source code control, and more! Their latest version, 2.6, adds support for IIS 7 and Zend Framework 1.7.3.
If you develop PHP applications, you should definitely head on over to Jcx.Software Corp. and spend the $99 to get your copy of VS.Php!