Found this "article" on Slashdot today.  Apparently the latest meet-up of XKCD Geohasher's has them meeting some ranchers that did not appreciate a bunch of strangers on their private property.

The ranger at the park service station was exceedingly friendly and said that the neighbor was just "easily excitable" -- I guess he must get really excited about shotguns. In any case, I think that we're probably in the clear, though anyone who wants to write an apologetic note to the hopefully-better-educated-less-having-of-chip-on-shoulder-Arkansas-visiting-property-owner should perhaps do so.

Looks like a lot of over reaction and a little common sense on the Geohasher's part to me.  Even the Slashdot people are critical of the geohashers.. which is amazing actually.

But it does lead to one important point, one that has been around for centuries..  Ask permission before doing someone on someone's private property.