Sand - 4:19 pm on Jan 22, 2013 (gmt 0)
I would worry less about the SEO and more about the business. For example, my site historically had registration CTAs at the top of the right sidebar. The standard for responsive themes is to shove the sidebar way down below the content, so my registration rates were abysmal for mobile visitors until I made some adjustments. Just make sure you keep those kinds of things in mind.