And you are all set... well... you are not :). IIS implements something called 'Socket Pooling' and if you have this enabled it basically makes IIS bind to all available IP addresses. So even when you go to the GUI and change the IP you want IIS to bind to, IT DOESN'T WORK. In order to make it work, you need to disable 'Socket Pooling', and you can do so with the following command:
script adsutil.vbs set w3svc/disablesocketpooling true
I just thought this was amusing and decided to make a post :). Something similar occurs with IIS 6.0 but I have not tried it yet. You can get more information here:
IIS 5.0:
IIS Binds to All Available IP Addresses When It Starts
How to Disable Socket Pooling
IIS 6.0:
IIS 6.0: Setting Metabase Property DisableSocketPooling Has No Effect