Cannot wait for Svidler's commentary (Jan's too, but less)! Dis is gonna be soooo gooood
As to the recent form of the candidates:
1. Karjakin - solid in Tata Steel, very sub par in London, bad in Tal's Memorial (Rapid), destroyed Tal Memorial (Blitz).
2. Aronian - was solid, but not spectacular, in Gibraltar and bad in London;
3. Ding Liren - apart from the Chinese league (mixed but overall dissapointing results), last important tournament was back in November, where he was decent in Fide Gran Prix in Palma de Mallorca;
4. Mamedyarov - recently two draws vs weaker players in Bundesliga, but very good in Tata Steel.
5. Grischuk - haven't played any elite tournaments in a while and in lower-tier competitions struggled mightily (including recent blitz/rapid at Tal Memorial).
6. Caruana - good/very good in London Classic yet absolutely terrible in Tata Steel right after. If he plays like he did in Tata he is clear "favorite" for the last place, if he plays like in London he has a shot to even win the thing. Biggest enigma IMO.
7. Wesley So - very solid, if not spectacular, in both Tata and London. I believe he is going to be in the upper half of the table, but is not going to win enough to take down the whole thing.
8. Kramnik - very good in Tata and my dark horse for this event. Incredibly, Vlad has become one of the most entertaining players in the elite these days, always a pleasure to watch.
So, overall, I honestly have no idea. Like Faustfan said, they are very evenly matched and no one stands out as a clear favorite.
If I had to make a prediction, I would go with:
1. Kramnik
2. Aronian
3. Mamedyarov
4. So
5. Caruana
6. Ding Liren
7. Karjakin
8. Grischuk
However, I would not be surprised at all if my entire prognosis is incorrect