additionally:
1. Apache does not (easily) support .net pages.
2. It is much easier to go get the latest Apache and install it, get the latest updates for php,ruby, etc and install them. IIS = buy licenses, activate, run out licenses (even if you really didnt just re installed, beg ms for more. this may reveal i am an iis admin newbie)
I have to say, having just gone thru the process of setting up an IIS server recently, and not having done it before, the first time I setup IIS it did not seem easier than apache, apache is just edit httpd.conf, iis seemed to be click all over the place, find mappings and so on and so forth. But subsequent installs of IIS were pretty easy.