Improve the contrast! The site is not very legible. At first I thought this was some kind of bad joke.

The site title overlaps with "Signup/Signin" when the browser window is too small.

The webfont in use looks horrible on Windows.

Edit: I recommend reading up on WCAG 2.0 (http://www.w3.org/TR/WCAG20/), this is a helpful tool: http://leaverou.github.io/contrast-ratio/