Out of curiosity, how did you know that the original URL copied the article from the current URL?
It's a press release, so I doubt Emory University minds much, but still, HN prefers original sources ("Please submit the original source. If a post reports on something found on another site, submit the latter." [1]), and phys.org and the other science blog-mills are problematic.
[0] http://phys.org/help/about-us/ [1] http://phys.org/partners/emory-university/
I see no real reason for the URL change either, since both articles are the same. Edit: The esciencecommons blog has many more links in the article next, never mind!