Search Engine Optimization (SEO) is all about design.
It is utterly amazing the number of websites out there that define their home page url, two or three different ways. How can you ever expect to succeed in Google, when your own home page is competing against itself?
Categories are born to be hierarchies. Using flat category structures is like shooting yourself in the foot.
Don’t be fooled into thinking that blogging with WordPress is easy. While anybody can put up a WordPress blog overnight, only a few can overcome all of the design and programming challenges necessary to excel with WordPress.
Most web developers create webpages visually with some type of WYSIWYG HTML Editor. In these types of visual editors, there is always more than one view of the hypertext document. While humans think in terms of the creative process of using pictures, different fonts, color, and size of print to create a pleasing visual effect; Google as a computer sees only the HTML source code view of what you have created. And, just like humans do to each other, Google discriminates against webpages based purely upon certain elements of the HTML view of your pages.
Did you know that ranking for non competitive keywords has more to do with the good SEO use of keywords, section headers, internal url structure and internal linking rather than with pagerank from external backward links?