Hopefully Zuckerberg (left), who spoke personably with complete strangers in the SXSWi conference hall immediately after his Sunday keynote, will bring that affability to an impromptu address today for a hyper-engaged crowd craving substantive talk from him.

According to someone who attended his panel just now, Robert Scoble told the room that Facebook founder Mark Zuckerberg will speak again today at 4:pm at Pangea in an unscheduled session here at SXSWi in Austin. Word has it Zuckerberg wasn't happy with how he came across in yesterday's keynote session with interviewer and SXSWi honorary persona non grata Sarah Lacy, and today's impromptu session will be an effort to correct that.

If this thing happens, we'll be there to bring back a full report. Stay tuned...