I still see Mayweather as a favourite.
Stylistically, Pacquiao has really struggled against Marquez, who is a counter puncher. In a very basic way, Mayweather is a bigger, faster and stronger version of marquez, countering his opponent, while also boasting a superior defence.

On the other hand Pac is a south paw. People keep on mentioning the Judah fight and saying Floyd can't fight left handers. I don't think 1 flight is enough to draw this conclusion. Mayweather adapted during the fight and won.

In my opinion, the style of the fighters make this more difficult for Pacquiao, but 1 punch could end it.