This is the sort of thing when technology products and marketing collide.
Apache already has a GUI for MacOSX, but on the non-server version it's very very limited. To get to the advanced features, you will have to either get used to editing the configuration file by hand, or step up to MacOSX Server. The server product does include a more comprehensive GUI for the advanced features of apache. Have a look at:
http://www.apple.com/macosx/server/theater/apache.html
As you can see, it's quite a bit more comprehensive. Apache is, to my knowledge, no different on the two platforms, but the frontend is certainly much different.
That said, it wouldn't shock me if someone came up with an Apache config tool for MacOSX that mimics the Server product. Then again, it wouldn't surprise me if Apple tried to block it. Again, marketing colliding with technology...
