I also really like what min aims to accomplish. These are my observations and recommendations to improve the site.
* h1 font-size should be around 2.2em. It's far too large at the moment.
* .contain width seems best around 1020px. You want a thinner width to improve readability.
* All buttons and clickables should not shift the page in any unexpected ways. Clicking on the buttons, for instance, go to the top of the page. One solution would be to onclick="return false;" on relevant elements.
* The "Min Basics" sections is a bit wordy. I think there's some superfluous information and I think the word count can be cut in half.
* The Download page doesn't cleanly separate the calls to actions enough for my tastes. I would prefer having a "CDN Delivery" section and a "Download" section. I believe most people who want a minimal framework will know the difference.
* The layout of the "GET CSS" button and the textarea seems...off. The button is too large and the textarea dimensions are, again, somehow off.
Other than that, I think you've done a great job explaining the benefits of your framework, have given a solid overview of is features and I appreciate the humor of the sea monster.
On the docs page, everything looks really big. It's a bit of a nitpick, but I think - in comparison to Picnic at least - it doesn't bode well for the default attractiveness of a site using Min.