Update #2: Check out my new post regarding the installation of Windows 8 Consumer Preview which should install even easier than this since it is meant to upgrade existing Windows installations. I have also had total success installing Windows 8 Consumer Preview in Parallels.
Update: Post updated for alternate workaround if the setup.exe file will not run. (Thanks Chris Apland!)
A lot of people have been asking if it is possible to run Windows 8 on Mac hardware through Boot Camp. I can definitely report at this time that it does work. You will need the latest Boot Camp drivers from Apple and a USB mouse with a dedicated right click button.
Once you have installed Windows 8 using Boot Camp, click on the Desktop tile. This will drop you down to the Windows 7 style desktop. From the drive that contains your Boot Camp drivers you are going to need to run setup.exe with compatibility settings for Windows 7. Otherwise, Apple's installer will detect an unknown version of Windows and fail to install. Right-click on setup.exe and click on "Troubleshoot compatibility".
After it Detects issues, click on "Troubleshoot program".
Check off the option that says "The program worked in earlier versions of Windows but won't install or run now" and click "Next".
Choose "Windows 7" and click "Next" to run it with compatibility.
Go through the Boot Camp wizard and reboot when finished. All of your drivers should now work! Don't forget to go into the Boot Camp Control Panel and turn on Tap to Click and Two finger right-click. Trackpad scrolling does work on the Metro-styled Start screen even though it doesn't seem like it at first. You actually have to scroll up and down instead of left and right.
What if setup.exe won't run because it needs Windows 7?
Well, there is a workaround that will probably work. Inside of the Drivers folder inside the WindowsSupport folder are all of the individual driver installers. You can try installing each of these manually and it may work for you. Chris Apland in the comments below had some success with this technique. Unfortunately, you won't get the Boot Camp Control Panel with this method.
Update: Still trying to figure out what is different with the 2011 MacBook Air driver package that is causing this process to not work correctly. I will update the post when we get it worked out.
Update: If you are having trouble with the process, try using the 32-bit version of Windows 8. For some reason this appears to work in cases where the 64-bit version did not. Seems to solve the problem with the 2011 MacBook Air. (Thanks Dewey!)