There's an interesting documentary called "Keepers of the Frame" airing periodically on The Documentary Channel. It's actually the history of film & how much has been lost to the volatility of nitrate stock, but it also covers weaknesses in the "safety film" stock that replaced it & efforts to salvage what remains.
Anyway, watching it reminded me of what everyone here is trying to do by shooting Kodachrome, & how well (or poorly) those images might be stored over decades.
Here's an in-depth
write-up of the film & some discussion with the director. You can also find the 70 minute film on Google videos.
Greg