He's not on the poster.....he hasn't been seen in the trailers.....or has he? I would like to draw your attention to this section of the trailer. We hear Han say, "The dark side.....the Jedi......they're real." Right when he says "...they're real"- who could that be with R2? I put my money on Luke. This should start where I indicated above- if it doesn't, go to 1:22.
I also noticed two music themes being played during this trailer and they are not rehashes from previous soundtracks. First we hear the love theme from Empire and Jedi and second we hear the 'force' theme (formerly known as Ben Kenobi's theme before there were sequels). I'm psyched! Woo-hoo!