This thread is very confusing and misleading, because Boot Camp has two parts, or "sides" if you will, and it reports different version numbers depending on if you're talking about when running OSX the "Boot Camp Assistant", or, what it installs into Windows 7 known simply as "Boot Camp".
As follows:
OSX Mountain Lion 10.8.2 = Boot Camp Assistant = .app version 5.0.0 (build 444). This is the OSX-side utility that paritions the OSX disk, lets you download the Windows drivers set, etc.
Windows 7 = Boot Camp Task Bar Tray Icon = .exe version 4.0 as reported in Help->About, or, version 4.0.2.0 as reported in File->Properties. This is the Windows-side utility that lets you easily reboot back into OSX, set the track pad settings such as enable right-click, etc.
I just got off the phone with AppleCare support, who confirmed that, as of today 11/1/12, the above-mentioned versions of Boot Camp are NOT 100% compatible with Windows 8, and furthermore that there is currently NO "officially" supported Boot Camp for Windows 8, period.
However, as found within these Apple message forums, there ARE some work-arounds to get it "mostly" working, by using wacky methods such as downgrading your Windows login permissions to User-level instead of Admin-level to get them to PARTIALLY run, etc.
Here is one such thread which has most of the "tricks" to get it "mostly" working in Windows 8 compiled into a single discussion:
https://discussions.apple.com/thread/4034572
I truly hope that Apple very quickly releases a new Boot Camp which is 100% compatible with Windows 8, to solve all of those issues for real... without hacks or other work-arounds as is currently required now.
Best of luck!