Marlette's court clerk, Barbara Freitas, said that the judge will publish a decision on Friday after an 11 a.m. hearing. Judges sometimes wait days or weeks to render a decision.
Marlette will not issue a tentative ruling ahead of time, however, according to a notice that the court issued today.
Judges will often issue tentative rulings before they hear oral arguments. In January 2009, Marlette issued a tentative ruling in favor of the governor's furlough authority prior to a hearing on the matter. What he heard didn't change his mind, and the tentative ruling became final. Furloughs started a few days later.
(Thanks to Blog User T for flagging the court notice for The State Worker.)