After 6 rounds, we're doing more or less the same as in the previous 8 scudetto winning seasons. In those 8 seasons, thrice we won full 18 pts, twice 16 pts (same as this year) and three times less than 16 points.
Only come mid-season we will have a better idea about our scudetto chances and rivals, because that's when we usually topped the table (although, on two occasions we were second after 19 rounds).
Anyway, what is mutual for all 8 previous seasons, apart from Juve winning them all, is that they were won by the team that conceded the least goals. The team that scored most goals in the season, won the scudetto only 2 times out of 8. The best defense won it 8/8. And while our defense was head and shoulders above everyone elses in the last 8 years, this Inter defense is a worthy rival.