Trending everywhere this way-hope it's true. But how can ON3 guy make a prediction w 60% confidence?

That is called a guess.

Probably more accurately, that is called "Other guys with better sources are making this prediction and i don't really have a clue, but I don't want to look bad by missing out. Therefore, I'll call it a 60% confidence prediction so that I don't look bad if the other people are wrong".