Mercer HR has a new Global pensions risk survey which looks at the way corporations perceive their pension plans with regards to their risk exposure. It contains a fresh view in so far as it doesn't consider plan coverage, but rather the risk that the sponsoring corporation is exposed to through its plan. Those risks are widely considered significant, with important differences between the US and Europe. Furthermore, a majority of corporations either doesn't know how analysts assess the impact of pensions on corporate valuations, or they think it's done inaccurately.
In the light of forthcoming pensions accounting that is set to better represent economic reality, this survey is relevant. It indicates that the market is already moving in that direction, but possibly also that risks are currently overestimated (or advantages consequently underrated) because of a lack of precise information about corporate pensions exposure and ways to manage it.
P.S. CFO.com has another good summary.