We've known for a while now that Nike is planning something big for Back to the Future Day, which arrives with much fanfare in a matter of hours. The biggest rumor, of course, centers around the launch of the futuristic Nike Air Mag. Nike sent a Tweet to Michael J. Fox with a coy message "see you tomorrow," followed by a Tweet from Nike Public Relations Director Heidi Burgett with a direct allusion to "self-lacing shoes." Could this be the harbinger of the shoe we've all been waiting for? Stay tuned.