Remember rule number one of investing is to be diversified..... also know what you own and why.
Blindly trusting anyone with all of your assets is just plain stupid. I know some people had everything under Madoffs roof, some had lesser proportions. It just drives home the point above even more of being diversified.
There are plenty of Madoffs out there, believe me. A scam the size of this can't be pulled off by one person alone. If Madoff sings, there will be a domino effect and many more individuals and institutions will get fingered.