Hear hear. Nothing strikes fear in my heart like a /usr/local hierarchy filled with a million random versions of random programs. BTW, if you are going to install something into /usr/local, at least use a cheap and easy packager like GNU "stow".
A user can manage his/her own stuff in ~/bin and add it to path if he/she wants.
A sysadmin can put things somewhere like /usr/local/experiment33 and make sweeping changes just by changing the default path, which a user could override for customization.
