weird font rendering issue in theme CSS

Throwing this up into the forum in case having another set of eyes clarifies what has been boggling my mind for hours now.

In the process of moving the design (via CSS) from one theme to another. The first is based on Zurb's Foundation. The second on Make from Theme Foundry.

As far as I can tell, both have the same essential CSS (colors, fonts, font weights) but they look rather different. Cannot for the life of me figure out why.

In the first screenshot, small sections from the two sites side by side. In the second screenshot, a zoom in with Photoshop which shows some radically different aliasing going on. Its as if there was some light text shadow affect surrounding the text.

Totally stumped!

Here are the two sites, in the same order as the screenshots: