There will be a sheet of ice in Fenway Park for a Jan. 1 Winter Classic. It's a done deal, Bruins vs. either the Capitals or Flyers. The league will make it official at the start of July, with a splashy media event in the old ballpark. NHL free agency begins July 1, which grabs headlines around league cities (except for Phoenix, of course) for 2-3 days. The Sox play at home July 3-12. If the league wants the day for full media attention, it likely will wait for July 13-14 to make official all details, including how to purchase tickets.
Nothing from the NHL yet regarding this, so nothing is official yet.