Here's an informative article I just came across. In short, SEO isn't just about getting your business to some point on a Google search; it's really a technological effort that needs to be refocused periodically and as part of your overall marketing strategy. So, don't fall for people who tell you "I'll get you on the first page of Google in x weeks." You'll pay them a stack of money, they'll go away, and your rank will be supplanted soon enough by some competitor out there, maybe in another part of the world. I'm no expert at it, per se, but I speak regularly with fellow web developers who are a little more up on it, and it's constantly changing due to Google's increasingly sophisticated search algorithms.
One great way to maintain interest is to incorporate your blog into your website, which can be done with an Atom/RSS feed plugged into your new site that reads content from your existing blog. Or, you can blog right inside the CMS system I use, as I do on my site.
In short, since SEO is somewhat of a dark, fluctuating orb of mystery, it should be discussed as a separate issue, somewhat removed from the basic design and functionality of your website. Let's get your website built while keeping SEO in mind, but don't let it become this overarching obsession that clouds your vision and gets a disproportionate allocation of time and resources.