Nice work on that 'sign-up for my newsletter', fullscreen, non-closable modal screen that pops up after reading a few paragraphs! Nice way to capture your adjacent users and convert them to whatever-core-something-engaged power customer.
Oh good, I thought there was something wrong with my browser that was hiding a close button. That's a very strange design decision.
Very strange, and a bad idea to boot! It is distracts from whatever point they are making in the article. The medium is the message!