I noticed that SAS changed the wording on the seat selection too. I booked a flight from Stockholm to Chicago, and part of my flight is on a SAS Saver Plus and after booking, the seat selction message had turned to 'Want a specific seat? Pay and reserve it now (free for EBG/EBD).' with 'Book Seats' button rather then a select your seats message with 'Select Seat' button.

When I saw this I thought, that I would have to pay for seats. I flew with SAS just last month on the same route with basically the same itinerary and could choose my seats in advance for free (apart from the front Go seats which did cost about 28.50 uk pouunds). Clicking the 'Book Now' button did allow me to choose my seats and for free so no waiting until I check in to select the seats but it seems a bit underhanded.