Sorry, but great SEOs are obsessed with SEO rather than conversion rate - that's why they're great at it. Concerned with conversion rate? Definitely. Obsessed? No.

Although conversion rates are massively important, unless you want to redefine what SEO means it is still about bringing more and better traffic to a site.

Conversion rate optimisation and search engine optimisation are two connected, though very different disciplines - and although a lot of SEOs might have an interest in conversion rate, very few could be called experts/specialists.

When you talk about an 'obsession' with conversion rate, it says to me that it's either all someone does, or the main thing they do. After all, it's an absolutely massive topic area - when you get into the realms of consumer psychology etc it's much bigger in scope than SEO. People like http://www.conversion-rate-experts.com/ could realistically be considered 'obsessed' with conversion rates.

Maybe internet/online marketers is a better term for someone with a holistic view encompassing both. As it stands, someone could be great at SEO but crappy at conversion rate optimisation.