There was a live fan chat sponsored by http://www.thecomicsreview.com & it was posted by a mod I know at LOST-TV that participated on Thursday night. Transcripts of hour-long chat:
Scroll down to post #9 by island_mav, who posted individual sections which highlight where Javi answered questions about LOST… or avoided answering some!
It appears that Javi did not give away HUGE secrets (of course)… but he was friendly, enthusiastic and gave away small hints, especially of when we would know certain things… and a pretty good spoiler hint about who the writer of the map was. He also talked very briefly about The Black Rock, “3 minutes,” and Ana-Lucia, and gave away some hints about those subjects as well.