As the article points out, the map is different in both as well. One shows CONUS, the other, the whole Earth.
Fits perfectly with the "different software" idea. Pages, Google Docs, OpenOffice and even different versions of Office produce different results with the same PowerPoint.
EDIT: Also, on the US-zoomed/masked one, it makes the ellipses line up correctly with all the cable landings at the coastlines. I'm now sold that these differences are just PowerPoint-specific renderings.
I'm marking this one down to PowerPoint-specific rendering (vs, say, OpenOffice).