[Guido]
If this isn't done, a problem might be (and this is why this is always done on Unix) that if the user who installs Python has more privileges than the user who uses Python, the user who uses Python may not be able to write the directory containing .pyc files, so they end up recompiling all modules each time they are loaded.
I expect this will be more of a problem as typical Windows users and installations (e.g. XP) become more security aware, software is installed by Administrator, and users don't have Administrator privileges.
I guess the way to implement it (and I believe Mark Hammond did indeed do this for win32all) is to run Python near the end of the installer with the compileall.py script as an argument.
Feeling-quite-the-Windows-XP-expert-lately,
Cool. If an organization has enough money to afford an administrator who installs stuff for unprivileged masses, they have enough money to pay Thomas to make this change <0.5 wink>. Mark once told me he compiles stuff at the end of the win32all install because generating Windows type libraries can take a long time, and users griped about feeling the pain of that on first use otherwise. That's a reason I can understand <wink>. If you can too, then it's more important to precompile everything needed for IDLE to start up the first time.