Earlier quoted context omitted.
I guess it looks better on your machine. This is how it looks like on Linux for me: http://i.imgur.com/JRHzYp7.png Extremely annoying to read.
That looks really bad. I use Linux as well, but hadn't checked the rendering in Firefox. Have to change it. Pity, it looked good in Chrome
Another version of the same font or the same font from another source may work. Webfont sites often try to tweak the hinting tables, they're trying to make the fonts look better but it breaks stuff all the time.