Alerted by PokeBeach, Gamespot’s E3 layout is indeed showing that Nintendo has plans to display at least some promotional pictures, videos, or materials regarding Pokemon Black and White. Frankly I would guess it to be trailers that we have already seen… POSSIBLY translated to English. Probably nothing too new for those of us who have been following Japanese sources already.
Also there is a possibility that the upcoming Pokemon Sunday segment may reveal more Pokemon. Time will tell I suppose!