The necessity of search engine optimisation (SEO) in making a website is apparent. At the very least, there's a usability component to SEO - if your customers, or potential customers, can't find the content, it might as well not be there.
SilverStripe's built in search-engine-friendly features (like hierarchical URLs and the ability to write good, clean semantic HTML templates) are a major consideration into what we're building out. Right now, one of our developers, Andreas Piening, is improving the Google Analytics module, so that one can more easily visualise Google Analytics data with SilverStripe.
SilverStripe also has an external links checker module, and if you want to check website performance (which also affects SEO rankings) there's the Dawn™ service.
We'll always have an eye out for SEO during development.
But one of the most important parts of SEO is often overlooked - that is, as effective as SEO can be for maximizing traffic, SEO can't help you generate traffic. You can't get more people to your website if you have no compelling reason for people to want to find your website in the first place. And for that, you have to create content.
There's an XKCD comic which illustrates this point perfectly - the "social media guru" talking about "building community" first - and says that "content will be discussed in part three." Sadly, having been to a number of seminars and talks on social media - this is too often the attitude of "social media professionals."
SEO can help, but the best and most effective way of building traffic is simply by creating compelling content. People come to SilverStripe.org because, quite frankly, it's a really great resource for finding out about (and downloading) the SilverStripe CMS. It has compelling value to the reader/user/visitor.
SilverStripe's focus on simplicity for the writer and editor is built around the idea that ultimately, the people visiting the website are most interested in the content. The goal behind our user interface is to make it as easy as possible for website content managers - even non-technical ones - to get the compelling ideas out of their heads and into their webpage, where people can see it.