You may have noticed already that some members of this forum are trying to create an IDE themselves. It may be interesting to join forces with them. The topic can be found here:
If you want to make you IDE a solo project, that topic still has some usefull ideas for your IDE, so you should take a look anyway .
Crebilis
Must read Review for Serious PHP Developers
NuSphere PhpED 5.0
: The Staff of php-editors.com recently spent a few days working with NuSphere
PhpED 5.0
(a popular PHP IDE) and
NuCoder 1.4
(a PHP Encoding Utility), read up on all the details.