Earlier this afternoon StumbleUpon founder Garrett Camp sat down at SXSW with All Things Digital's Liz Gannes to talk about a social media company that drives a huge amount of traffic on the social Web. Fun fact: It delivers more than 1 billion personalized recommendations per month. Unified and @visualhero where there to capture the session. (Disclosure: StumbleUpon is one of Unified's partner for the ongoing drawing coverage of South by Southwest.)