So I've tried a hundred different methods to bridge my Xbox to my Mac. Internet Sharing from Airport to Ethernet is enabled, and I've tried things such as using the inet++ as the IP and the inet itself as the gateway. I've tried using my Airport's DNS settings. I've tried using my router and computer's IP as the DNS settings. I've tried using public DNS sources like openDNS and google's DNS addresses. I've also tried giving ethernet its own IP address in my computer's preferences and then using that was the gateway and that +1 as the IP address for the Xbox. And so on and so forth.
I've followed a dozen tutorials, but my Xbox is never able to resolve the MS servers and connect to the internet (it can only establish a connection to the network).