QUESTION :
Is the home directory variable for Windows 8 the same as it was for Windows 7, %UserProfile%?
ANSWER :
To get a list of all currently define environment variables, just execute the following command:
set
Windows 8:
Winkey +r
%userprofile%
Result: Explorer launches showing Appdata and My Document folders plus all the others.
To get a list of environment variables launch PowerShell and try:
Get-Item env: