It's a result hardly anybody has yet predicted in 2008, and it's easy to see why.
Massa's start to the season was erratic, with retirements in Australia and Malaysia. He's taken far longer to get to grips with the new Ferrari than his teammate, Kimi Räikkönen.
But on recent form, Massa looks to have the measure of his champion teammate. It remains to be seen whether the Brazilian can keep this form up for the whole season.
If he can, then don't be surprised to see him emerging at the top of the standings after his home race in São Paulo at the end of the season.
Don't forget, it was largely bad luck that put Massa out of contention for the 2007 title. This is not to take anything away from Räikkönen—his consistency towards the end of the season was immense, and he thoroughly deserves his title as world champion.
But how quickly we have forgotten that Kimi was behind Massa in the standings for almost half of the year. Without Massa's unlucky qualifying incident at Hungary, his suspension failure in Italy, and his pitlane disqualification in Canada, he could have been right up there with Alonso, Räikkönen and Hamilton.
Now, after six races of 2008, he finds himself just one point behind his teammate and with the upper hand in terms of form. We know that the Ferrari is faster relative to the McLaren this year, so there's good reason to think that the Ferrari drivers are best placed to win the world title.
Massa has silenced his critics lately with excellent drives. Everyone was surprised to see him on pole last weekend at Monte Carlo. His Monaco run was soured only by a small off at turn one.
But given that all but two drivers made some such error, and the huge margin by which he beat his teammate, that should be forgiven.
If Massa keeps surprising people by putting his car at the front of the grid, and driving the excellent races that we know he's capable of, then there's no reason why he shouldn't be the first Brazilian world champion since Ayrton Senna.