Edit: I didn't realize it said you would be taxed 70% on income above 10 million, I was thinking it was 70% of 10 million. Yeah 10 million (or 6.5 after normal taxes) in one year is plenty.
I think America is fueled by the dream of "making it big". I believe we should all have that opportunity and so I think these income taxes should take effect on the second year that your income exceeds the threshold, but that you should pay a lower rate for the first year. People invent things, they write stories, make movies, win at gambling... Those people should be allowed to enjoy their success, not be punished because their payout came all in the same year.