Mika Salmi, the former global digital head for MTV Networks/Viacom (NYSE: VIA), has joined Sulake, the parent of the virtual world Habbo, as Chairman of its board. Ever since leaving MTVN earlier this year, Salmi has been on an extended break from work, but has kept in touch with the digital world through his various board — BlinkBox, Inkd among them — and advisory roles. This is his first major hands-on gig since then. Sulake is among the only private social media/gaming firm that announces its earnings. For 2008, it had about $74 million in revenues and $7 million of EBITDA, based on its sales of virtual good within the virtual world, and advertising.