"...and enforcing sandboxes is going to be much more difficult in that environment." This is the approach they're taking. The sandbox for applications sold fro

"...and enforcing sandboxes is going to be much more difficult in that environment." This is the approach they're taking. The sandbox for applications sold from the Mac App Store will be required from a certain date (which was pushed forward due to concerns, if I remember correctly) and will be quite strict in what it allows access to. Mountain Lion will include the Gatekeeper, which defaults to allowing applications from the App Store and applications which have been signed by Apple. While signed applications don't get their code checked, their certificates can quickly be revoked if Apple finds any malicious activity. (See: https://secure.wikimedia.org/wikipedia/en/wiki/Gatekeeper_%28OS_X%29 https://secure.wikimedia.org/wikipedia/en/wiki/Gatekeeper_%2... and it's references) The good thing is that they still allow anyone to change the Gatekeeper-settings to allow any kind of applications, signed or unsigned. Had that option not existed, I bet we would be seeing a migration from OS X by developers. Most average users will probably keep the default setting, giving them a (in theory) quite risk-free environment.