Nice graphics! I really like from-the-bits-up explanations of things like this.

I found the newsletter upsell in the sidebar very distracting. I know you're considered a fool if you fail to bash people over the head with newsletter sign-up requests these days, but maybe just keep the ones interspersed in the text and get rid of the one I have to see all the time? Or I guess AB test it or whatever the cool kids are doing for this stuff. I dunno, but it really detracted from what I otherwise thought was great content.

Best of luck to you!