There's certainly a gap in the market for the site, with LGHEI (the Lesbian and Gay Hospitality Exchange) having failed to have seized its position as one of the hospitality movement's originators. LGHEI, pronounced El Gay, now looks seriously dated and a membership of just a few hundred makes its future look dubious.
The bare torso on Surfing Sofa's current homepage certainly gives the site more of a dating-site feel than Couchsurfing. "Do I have to have a fling with my host?" is another FAQ. No, there's absolutely no obligation - is the answer. Although there's a clear subtext that they expect a whole of that to be going on.
Nonetheless, it's a slick looking site. We'll have to see how it fares.
Perhaps their oddest decision is choosing to call their ambassadors "slaters". The site's explaination: "The name is making reference to Kelly Slater the number one surfer in the world." I guess it must have seemed like a clever idea at the time.