I think SEO has had its day, and that this forum is a clear reminder that clinging to the same outdated notions of what SEO was does you very little.
Yes, we all say that content is king, but ultimately content will only get you so far. The inconvenient truth is that backlinks are the key to success for SEO, and that this is something a lot of people think is very easy to game. All the spammers come onto here asking for the best ways to get loads of backlinks without realising that Google has some of the best minds in Computer Science working against their methods. SEO is neither an art or a science. It is a methodology of growth, and as Google slowly but surely reduce every avenue for spammers we'll see online marketing and social media become a much stronger force.
SEO still has its place, but mainly as a set of rules that govern how a site should be run and managed. The off-page aspects of SEO are handled much better by marketing and ad agencies nowadays and as such the demand for genuine SEO is slowly dying out. It's one of the many reasons why this forum no longer has a dedicated SEO forum, because the demand for SEO is dying and because the subject is notorious for spammers.