Thanks for bringing this up, I just cancelled my download. There is no way I'm going to run an OS that attempts to limit my power to delete or modify applications. I think this may be the final straw for me and OSX.

I very recently had to attack GarageBand with a hex editor to disable app sandboxing so I could use third party VST plugins. I realize System Integrity Protection can be disabled by a kernel boot param, but this really, really, sticks in my craw.