Social Media Optimization vs. Social Media Marketing

Social Media Optimization vs. Social Media Marketing
"
In Social Media
Social Media Marketing (SMM) and Social Media Optimization (SMO) are two new phrases that popped up last year to define marketing through social media and social networking sites. There seems to be a lot of confusion about what each of them mean and what exactly they define, which is bound to happen with any new phrase.
Even when potential clients contact us there seems to be a lot of confusion between the two. I see them as two different emerging marketing techniques. When the phrase Social Media Optimization was first invented by Rohit Bhargava, some people didn't agree with the phrase and instead suggested that we rename it to SMM.
I'm not trying to point fingers at anyone though, even I am guilty of making the same mistakes; when I jumped on the original SMO meme-wagon and added some rules of my own I added one about creating viral content. I would no longer classify that rule as SMO and instead would now classify it as SMM. In my opinion creating something new is more about marketing than it is optimization. In light of this confusion, I am going to make an attempt at clarifying the two phrases.
SMO refers to the process of refining a website (optimizing it) so that it's awareness and content are easily spread through social mediums and online communities by users and visitors of the website. This can include anything done "on-page" such as improving the design and usability of the website so that it becomes more compelling to users, in an effort to help them spread it through social media sites. The simplest example of SMO is represented by all the "digg this" and "add to delicious" icons and links that are all over the web today.
SMM on the other hand plays more of an active role in relation to social media by referring to the creation and distribution of content and other messages through the social web by some form of viral marketing. This can be anything from creating compelling content that gets bookmarked and even hits digg's homepage to spreading a viral video by putting it on YouTube and other social media websites. It's about the things that are done off-site, for example, participating in online communities where your customers hang out would be an active role that falls under SMM.
In some ways the two remind me of the differences between push vs. pull marketing. But only a little bit, and I have to be careful what I say here. In a way with SMM you are actually pushing your message out there, but that's usually where the pushing stops. Once you push that message out there it should not require any more pushing. A true viral marketing campaign is so good that it spreads on it's own and people actually want to spread it, so the push usually ends with the creation and initial "planting" of the campaign. SMO is all about pulling people in with an "optimized" site and encouraging visitors to spread your content without any effort on your part. I think the clear difference between the two is that SMO refers to on-page modifications (on your website) while SMM refers to activities that take place outside of your website (on other websites). As I see it, SMO can be one of the ways to encourage SMM activities by users and visitors of your website.
I would love to hear what other people think about these ideas about social media optimization and social media marketing, does my explanation make sense to you, or do we need to go back to the drawing board?