Windows 8 Consumer Preview Invalid major version?

I use this code to detect WindowsVersion on a PC.

function GetOS: string;
var
 osVerInfo: TOSVersionInfo;
 majorVer, minorVer: Integer; 
begin
Result := 'Unknown';
osVerInfo.dwOSVersionInfoSize := SizeOf(TOSVersionInfo);
if GetVersionEx(osVerInfo) then
 begin
  majorVer := osVerInfo.dwMajorVersion;
  minorVer := osVerInfo.dwMinorVersion;
  case osVerInfo.dwPlatformId of
  VER_PLATFORM_WIN32_NT: {Mirosoft Windows NT/2000 }
    begin
      if majorVer <= 4 then
        Result := 'Win NT'
      else if (majorVer = 5) and (minorVer = 0) then
        Result := 'Win 2k'
      else if (majorVer = 5) and (minorVer = 1) then
        Result := 'Win XP'
      else if (majorVer = 6) and (minorVer = 0) then
        Result := 'Win Vista'
      else if (majorVer = 6) and (minorVer = 1) then
        Result := 'Win 7'
      else if (majorVer = 6) and (minorVer = 2) then
        Result := 'Win 8'
    end;
  VER_PLATFORM_WIN32_WINDOWS:  { Windows 9x/ME }
    begin
      if (majorVer = 4) and (minorVer = 0) then
        Result := 'Win 95'
      else if (majorVer = 4) and (minorVer = 10) then
      begin
        if osVerInfo.szCSDVersion[1] = 'A' then
          Result := 'Win 98SE'
        else
          Result := 'Win 98';
      end
      else if (majorVer = 4) and (minorVer = 90) then
        Result := 'Win ME'
    end;
  end;
end;
end;

For some reason, he says that the Windows8 Consumer Preview Build 8250 (32 bit) is Windows XP - the main version is 5. I checked and should be version 6.2 (according to notepad.exe on windows8) Is this an error or something wrong? By the way. my windows 8 is up2date.

Any ideas?

EDIT: ScreenShot