“there must have been a high degree of returnees”
This, I think, is a valuable indicator as to the quality (and success) of a conference. Unlike conferences like DLD, which are invite-only and therefore (have to) invest money in VIPs and who-is-whos for great PR, conferences like lift don’t need all this fuzz. Returning attendees is about the best positive PR possible; it’s free and quite a reliable measuring tool as to the quality of the conference itself.
“i.e. we were all blogging and twittering about the same presentations”
I told, er, twittered you so. You, the Scoble and Stephtara had quite a Schnittmenge of observations. 😉