How you optimize your website for the search engines will depend on whether you're considering your phone friendly customers or your desktop based clients. It gets a little tricky and this is one reason to consider mobile sites vs. responsive sites. Here's what I mean.
First, let's clarify the difference between responsive and mobile. We define a mobile site as a separate instance of your website specifically developed for a phone. It is an application that runs on your website.
What is Mobile? What is Responsive?
A responsive site is a reorganized format of the exact same information that is on the desktop version. Even the graphics will resize to fit the width of the phone if the responsive design is good.
Now, considering search engine optimization, let's please, for the sake of argument assume the search engines (especially Google) know what they're doing. Ultimately they are trying to rank sites in order of relevance against the search term that the user entered. The first question that comes to mind, is do you search for stuff on your phone like you do on your desktop? The second question is do you expect the same results. If so, do you respond differently to the search depending on whether you're on your desktop vs. your phone.
Do you search on your phone the same way you do on your desktop?
The answer is probably no. And you don't even think about it sometimes but apps are giving you access to searches in ways you never thought of on the desktop. You look for restaurants on Yelp. Every local news site and radio station has their own apps for local weather, news and they all promote local businesses. You listen to Pandora or iHeartRadio and they offer up their own local advertising. Groupon, Living Social et al and yes all the social media sites are providing search options that were only secondary on your PC. A lot of your clients LIVE on Facebook? (are you there?). In fact, if Google is going to exist in this world, it has to be relevant in the mobile market. Now you know why Google will be penalizing sites who are not mobile friendly!
Do you expect the same results? And do you respond differently?
The answer is yes and yes. If you're looking for local gyms, you want to see that list but ultimately you want to get right to the point. You're not reading a novel. A bounce is defined in Google analytics as someone who landed on a page in your website and left without going to another page. The bounce rate on mobile is considerably higher. In other words, the information the client finds on that landing page better be relevant or they're back looking for someone else. This is where responsive design could be a hindrance. If your home page covers all the bases of your website, it could be way too much for a phone. If the visitor can't find what he or she is looking for in a matter of SECONDS, it's a dud.
Just the beginning of mobile SEO and web design
The fact is, businesses are still in their infancy relative to how to present a mobile site. Most web developers will include responsive design simply because something is better than nothing. Responsive design is a bit lazy (frankly). It ignores the difference in expectations associated with the mobile versus desktop user but in a world where most small business do nothing, it's better than that! Mobile sites have their own pitfalls. They must be separately maintained. The must be separately optimized. Ultimately, we've only seen just the beginning of mobile website development. Jump on board now though because Google isn't going to wait for you to figure it out.