As I mentioned before City is estimated to have 52% of winning, Arsenal: 23% and the chances of a draw are 25%.
The big reason for that is that City will be playing home, and so far, in this season, they haven't lost a single game playing in front of their own fans.
Home/away stats for both teams (W-D-L):
Man City:
Home: 10-4-0
Away: 9-2-3

Arsenal:
Home: 11-2-1
Away: 9-2-3

Arsenal has slightly better stats of both goals scored and lost, so my personal prediction is a draw, but I'll be rooting for the City to win.