I totally get why people delivering great content want to maximize their readership this way, but I've never read an article on that site before, so how would I know if its worth giving my email?
@Kye - After seeing the crap that comes on the History Channel, I don't know if I can trust anything anymore. National Geographic might just become National Geothermal Signatures of Alien Presence... But that's just my ignorance of NG speaking.