This wasn't clear in the promo but WWE has noted that the challenge was for next Friday's SmackDown on FOX premiere from Los Angeles, which will also be the SmackDown 20th Anniversary special.
Owens noted that Shane's lawyers will draw up the documents and place them in a briefcase, to be hung above the ring during the match. If Owens loses, he will stay "fired" and drop his $25 million wrongful termination lawsuit against Shane. If Owens wins, Shane will be forced to leave WWE.
WWE has not confirmed the match as of this writing but stay tuned as we will keep you updated.