As of this very moment, there have only been 4 players to score 90 or more points and win the Selke in the same season (Troy Murray - 1986, Doug Gilmour - 1993, Sergei Fedorov - 1994 and 1996, Pavel Datsyuk - 2008 and 2009). Kopitar will probably be the 5th and in my opinion, he should become the 2nd player in NHL history to do accomplish this feat and win the MVP in the same season (Sergei Fedorov - 1994).
This is how good of a season Kopitar had, to put it in a historical perspective.
Now, think of what it should take to trade for a player of that magnitude.