SEM is a complicated industry with various disciplines. There are firms specializing in different areas of the industry from traditional SEO, to PPC to content development to link building. In fact, it's becoming more and more rare to find a company that does all of these in-house.
And this is why I think SEM is similar to being a doctor or lawyer. Not because we have to go to school for years and years, but because we are always learning. In fact I think I don't believe we do search engine marketing. As with doctors, we practice it.
I say practice because we can never know all there is to know about SEM because it is always changing. Maybe this is why so many in our industry use a phrase near and dear to my heart: It Depends.
If you subscribe to the micro persuasion model of public relations, then you would agree that the Internet is the new frontier in marketing. Blogs are increasingly becoming the medium of choice for companies and entrepreneurs in bringing their brands and products closer to consumers. E-commerce sites are fast becoming widely-accessible, and a variety of products can now be purchased online, from clothes, to computers, to cars. The World Wide Web is one big conversation, and companies are vying to join in, get to talk back, and get feedback in return.
The essential thing for a company to do is to initially create an online presence. As long as you're there, online and accessible over the Internet, people are bound to seek you out, in their quest for information. Imagine how much more business you can generate if you actively pursue marketing activities online. Imagine if your company website or weblog comes out as number one in Google for a generic search on your product or service. You can literally bring your brand closer to hundreds of millions of people who go online.