A report has been given that the ABC Network will not be running any promotional spots, teasers or any press of the like for the final season of Lost. That being said, I did find official poster art that will seem to be the only press material for the upcoming season.
Pictured is entire cast of Lost, with John Locke (or 'not' John Locke, as it were) with his back to us. Look closer, and you'll see there are hieroglyphics in the title. They roughly translate to "Who is our saviour?" or "Who is our leader?"
Thanks to lostargs.com for the poster information. Enjoy!