If Aronian wins he will equal Carlsen's five Tata victories.
Tata 2017
Just how impressive Aronian's 4 and Carlsen's 5 tournament wins in 9 Tata starts are one can see by just looking at for example Kramnik's last ten finishes in the tournament: 3,2,3,4,6,4,4,7,2,5

Is it just me, or does the field look slightly weaker than usual?:
Carlsen
Aronian
So
Karjakin
Harikrishna
Giri
Nepomniachtchi
Eljanov
Wojtaszek
Andreikin
Rapport
Wei Yi
Adhiban
Van Wely
Carlsen can win it for the sixth time, and I think Aronian and So are the only other players with reasonable chances of stopping him. Aronian usually does well in Tata, and So has been doing well recently, but maybe lacks some sharpness to win here. My guess is 1.Carlsen 2.Aronian 3.So 4.Giri 5.Nepomniachtchi 6.Karjakin 7.Eljanov 8.Wei Yi 9.Andreikin 10.Rapport 11. Adhiban 12.van Wely 13.Harikrishna 14.Wojtaszek
Ratings-wise it doesn't look very weak to me. Maybe it's that in the past the players in the Harikrishna/Eljanov/Wojtaszek range in the world rankings were guys that we are more accustomed to seeing as winners of major tournaments, or at least tournaments that we know of (Mamedyarov, Ivanchuk, Giri a few years ago, etc).
"Ratings-wise it doesn't look very weak to me"
No, the average rating is after all 2750+, but players like Caruana, Anand, MVL and Naka would have been nice to see. Kramnik too, of course, but it's been six years since he participated.

I didn't think Aronian performed that well in the major tournaments in 2016 compared to Anand.
Anand scored great results last year, with a plus in all the top tournaments he played, Candidates, Sinquefield, Tal Memorial and London, finishing at worst shared third. Aronian is much more uneven, but when he is in form he can win the strongest events even with Carlsen present, like Tata 2012, Tata 2014 and Sinquefield 2015.
Is it just me, or does the field look slightly weaker than usual?:
Carlsen
Aronian
So
Karjakin
Harikrishna
Giri
Nepomniachtchi
Eljanov
Wojtaszek
Andreikin
Rapport
Wei Yi
Adhiban
Van Wely
Carlsen can win it for the sixth time, and I think Aronian and So are the only other players with reasonable chances of stopping him. Aronian usually does well in Tata, and So has been doing well recently, but maybe lacks some sharpness to win here. My guess is 1.Carlsen 2.Aronian 3.So 4.Giri 5.Nepomniachtchi 6.Karjakin 7.Eljanov 8.Wei Yi 9.Andreikin 10.Rapport 11. Adhiban 12.van Wely 13.Harikrishna 14.Wojtaszek