Nole will be back, which means neither Federer or Nadal will win another slam again.
Nole will win 3 slams minimum in 2018.
NOT evey player (not even Novak) can be Roger. Roger is a NATURAL (and I am a Rafa fan). He can wake up and come to the court and win. LOT of fans have a "hope" that somehow Novak will do a Roger just because he took a break ala Roger.
Let us wait and see if Novak returns and then see how he performs at AO.
2017 season is still not over. If AZ manages one more Masters' and if another youngster (say Shapovolv) dies well in some of these, the dynamics can change for 2018. Too early to talk about 2018. Roger, Rafa are on the wrong side of 30, Novak and Andy are in mental and/or physical slump..
JUST like 2017, 2018 can surpris us.