Now for the negatives:
those gradients in your main navigation ( ABOUT, DOWNLOADS, etc... ) is horrible. I see this a lot in bad Wordpress themes. It's dated, looks bad now, and will look worse in 6months.
The blue SEARCH font color on the blue background is a poor contrast choice.
Those Python 2.x, 3.x buttons look terrible too. It's the gradients, remove those inner grey gradients, it doesn't add anything to the buttons, doesn't even make them stand out.
Your code formatting screen looks great.
The responsive layout also needs work. The double navigation bar on ipad doesnt look nice. The search bar on the iphone is WAY too small. that should either be stacked / above / below the nav, not side by side on a 320px screen.
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web design is going flat, with big font types, and big images, everything is square, clean.
http://www.hulu.com/ http://www.uniqlo.com/us/ http://www.ebay.com/new http://www.ign.com/articles/2012/11/05/the-walking-dead-kill...
Personally i would keep it simple like backbone documentation
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Good job though :)