I am a little confused. PHPNuke? I checked it out, but does PostNuke not use PHP/MySQL anyways?

PostNuke 0.7.2.3

Well, I plan on using PostNuke. I am testing it out with 5 different forums.

VBulletin v2.2.9
UBB.Threads v6.2.1
YaBB SE v1.5
Invision v1.1
phpBB v2.0.4

Please reply with any info you know about these. I will review and rate them.