New update posted today:
http://airlineroute.net/2013/01/10/tg-s13update3/
ARN will be operated by 777-300ER completely from the summer and CPH will have both 747 and 777.
Checked on certain dates in July, the new seat maps are loaded, but sometimes the aircraft type is still showing 747 even though the seat map is 777.
Interestingly, TG do not seem confident in premium yields from ARN/CPH and have opted to sell half the business seats as premium economy. I always thought the TG premium economy was only a stop gap measure due to the old 747 All Series product.