Why GM IPO is vastly overpriced at $1/share

"Workers lived a lot longer than they were expected to.  Those factors mean that the ratio between retirees and workforce became extremely lopsided; at the moment, GM has a little over 50,000 hourly employees--and about a half a million retirees.
That left the pension badly underfunded...Meanwhile, soaring health care costs were making the health care benefits even more of a problem than the pensions."

http://www.theatlantic.com/business/archive/2010/10/new-gm-same-old-union/64088/