In lieu of an E3 press conference, Nintendo is going to present a Nintendo Direct before E3, showcasing the "new Smash Bros., 3D Mario game, Mario Kart and other Wii U titles."
The company previously announced that all three games would be playableat E3. This means for those not attending the show, the games may be playable at Nintendo's special Best Buy E3 demo extravaganza (note: fullness of "extravaganza" is TBD).
The most recent Nintendo Direct held last week covered the company's summer plans and Hedgehog snuggles.