Eric,
I'm a long time C++ programmer (since '87, C since '77
), so I know the power of a full OO language. If I was doing a major web project, on the scale of cnn.com or yahoo.com, with a team of developers, such tools would be useful.
But for the projects I work on, the power would be overkill. Things like the stores at photogregg.com and contentbroadband.com and most projects I've seen on the adult web, the power is overkill and PHP/Mysql works very well. The only thing missing from Mysql that I would want is transactions and the latest version has that. Or I could switch to Postgresql for them.
The OO features of PHP are quite adequate for smaller projects and I very rarely miss things like templates and such.
With Security as you say the admin can keep a system secure. But it's the undiscovered holes I worry about.