While it's frankly a pity to have the tournament decided by tiebreaks (a perspective I'm guessing both Vladimir Kramnik and Fabiano Caruana share) it did make for an exciting final game between Sergey Karjakin and Fabiano Caruana. Provided that Viswanathan Anand didn't manage to defeat Peter Svidler with the black pieces (and he didn't, and didn't come close to doing so), Caruana would need to defeat Karjakin with Black to overcome the latter's favorable tiebreak score.
Winning to order with Black isn't easy, in part because White has many ways to dry up the game if he so desires. Caruana opted for the Classical Sicilian, and managed to get a complicated game with good chances. All three results were possible as the players grew closer to the time control, and the critical moment came on move 36. Had Caruana played 36...Be4 or 36...Bf3, anything would have been possible, but to his misfortune he spotted the tactical possibility 36...Re4, which apparently retains an extra pawn. Unfortunately for him, it lost to the nice rook sac 37.Rxd5 - an especially nice find by Karjakin under the circumstances. After that, Caruana was simply losing, and resigned a few moves later, when it was mate in three.
An excellent win for Sergey Karjakin, who deserves congratulations on winning the event - especially for bouncing back after losing to Anand in round 11. On now to the World Championship against Magnus Carlsen this fall in New York. In general Carlsen has a huge plus against Karjakin in faster games, but in Classical chess his plus score is a relatively moderate one: +3 -1 =14. Karjakin is a better theoretician and a better defender, while I'm inclined to give the other edges to Carlsen and rate him a clear but not overwhelming favorite.
That's many months away still. For now, here is the last round game, with my comments.