I have the same problem as it was reported some time ago. My email mslama@email.cz does not work (ie. I get got registration email but no api key email even if I tried repeatedly). Other email sotek68@gmail.com works. 3rd one mslama@idc.com does not work. I get registration email but not api key email. And yes I checked spam/junk folder.
I am trying to start new thread because my comment to http://www.opencalais.com/forums/geek-speak-technical-usage-and-issues-questions-and-hints/api-key-never-sent#comment-4549 was not added.
Marek