I think also that their idea of what constitutes 'wet storage' is wrong, or at least over-simplification - 80% in and of itself isn't the issue -- the tea can probably handle short term spikes much higher than that. The issue is sustained storage in overly humid, non-ventilated environments, or intentionally spraying tea with water to speed up the aging process. Some people like the results of that; others don't.
There are already a lot of discussions on the forum and elsewhere about storage, wet or otherwise, so have a look around.
For starters, check out Marshaln's bit on it here:
http://marshaln.xanga.com/682032582/wha ... t-storage/
also:
http://www.teachat.com/viewtopic.php?p=98975 (do a Google search for site:teachat.com wet storage and you'll probably get some more results)
http://www.teadrunk.org/viewtopic.php?id=20
As to whether it's unhealthy or not, I think that's still up for debate, but millions of Cantonese seem to be hanging in there, wet-stored pu'er or not, and tea that's wet-stored (by the definition above, at least) describes most tea in the long history of pu'er tea, so I think we'd know if it were really unhealthy. I would say if there's nothing too weird growing on it (besides those little white mold specks), it's probably safe to drink.