I don't know is that only my problem or not but I have a little eyestrain when using Fedora (19) with Gnome 3(.8) compared to Ubuntu, Linux mint or Windows.Maybe the problem is caused by font rendering or anti aliasing or even the fonts themselves. I think the fonts are sharp. I cannot explain that but I believe that it's different from Ubuntu.  
non-smooth fonts in Fedora's gnome
fedora;gnome;fonts