Just woke up and saw that teaser trailer and noticed the book on the desk titled 'Seven Pillars of Wisdom'; which is a book written by T.E. Lawrence (lawrence of arabia). :D So that's a fairly good indication that there will be a lot of sand in Uncharted 3.
Edit: Watched it again and saw the map that had 'ARABIA' written right across. (slaps forehead) Bah, and I thought I was being all detectivy T_T (eats breakfast) .