The Ongoing Debate: Should internet-facing TMG/ISA be a domain member or a workgroup member?

I have recently delivered a presentation on whether to join a TMG/ISA server to the domain or make it a Workgroup member.

I have shared it on SkyDrive, Download it here

Important I would like to append to this presentation, whatever you do, do not log on with high-privilege accounts (ex: domain admin) to an internet facing server. You could be vulnerable to your credentials hash being reused by an attacker, which is dangerous for high-privilege accounts.