I'd favor government pensions - an extension of Social Security if you will. Allow professional gamblers (nay Financial Professionals) to handle this fund. It would follow you. The plain fact of the matter is that the 401(k) system is a complete and utter failure. It in no way compares with the pension plans of old. But I agree that the pension plans of old cannot be trusted to private enterprise for the reasons we've already listed here. I say, take the monies we are currently blowing on the Wall Street 401(k) fund managers and put it into a government fund with our names attached (much like Social Security). Let the managers work with this enormous pool of money - who knows? There might even be some legitimate investment coming out of this instead of the 30 year established Casino Capitalism of Wall Street.
Even now, if the companies you worked for had pension plans, you wouldn't be completely without income. True, you would not have fared as well as the limited number of folks whose pensions were not raided, but you'd be getting at least something. What if your 401k was handled by somebody like Lehman? Or Bear-Stearns? And lest we forget, the remaining investment banksters are only still alive because of taxpayer money.
In this much I think we can agree: pension funds will always be too juicy to trust to the greedy capitalist money class. They must be handled by genuine representatives of the people. Put another way (and here we may differ) given the choice between the two, I'd put the government in charge of my money far and away over Wall Street.