Can you hire an SEO consultant to build a strategy for your biz?

Typically the only thing that changes in SEO is the blackhat methods that are trying to manipulate search ranks to give a ranking to a site that frankly doesn't deserve it. The reason they change is because Google is constantly discovering them and destroying their effectiveness.

Meanwhile, people doing whitehat SEO have been doing almost the same exact things for years, often to great success.

The only part of whitehat SEO that really changes is when new technologies are added, it can be useful to add them in. For instance, Google is really pushing people to add G+ buttons to their pages nowadays. Adding a G+ button is a relatively new development that is definitely whitehat and probably helps a tiny bit with your rankings.

Other than new technology developments, whitehat SEO has been the same for years: make great content that provides great value to the person searching for it, and be sure to focus the page on some decent keywords or at least on a general topic that people are searching for.

In fact, I just stumbled across this blog yesterday where the author of the blog did an experiment: he decided to follow only Google's guidelines for SEO. That means just creating great content and building no links himself. And wouldn't you know it... he had something like a $5000+ month after 6 months of doing this strategy.

It's constantly evolving and if you don't keep up you are left out.