He's not a hero for writing this letter, he as to be treated with circonspection, and at best given a second chance under close watch.
(Though cynical-me wonders how much of it is heartfelt and honest, and how much of it is carefully engineered spin - crafted and chosen by a team of psychologists/marketers. About the only admirable thing about Groupon, at least to me, is their magnificent use of language to persuade and influence both buyers and sellers of Groupon deals.)
This is what Andrew Mason was like. He was one of the high points of working at Groupon.
Assumes he wrote the statement and wasn't helped by PR people of course. In that case he gets credit for at least listening to those more experienced than he is.
Can't tell without seeing his reaction in other situations that are similar of course.