Final Word
Snit There is no "regedit32" but buttuming you meant regedt32 and regedit they execute the same program. I just type "regedt32" from years of habit. In days of past regedit would allow...
OS X has as many logs as you configure it to have and if a process decides not to write to the log, it leaves no trace here.
Meanwhile it's often binary XML, which is not *that* human-readable at all.
Every installed file? No. Only stuff that is installed with the installer and even apps using an installer sometimes just create files from within scripts and copy them somewhere. No trace left anywhere. In fact the scripts deployed by an installer can do *anything* without leaving a trace.
If this were true there were no rootkits for Unix systems.
Malware can (and does) hide from view even on Unix systems.
I do not say that OS X is not more secure than Windows, but it's in no way totally secure.
Jochem
-- "A designer knows he has arrived at perfection not when there is no longer anything to add, but when there is no longer anything to take away." - Antoine de Saint-Exupery