I agree with the other guys in saying this isn't text book 'high key'. If he was wearing a white shirt, then maybe.
But really, I don't like to worry too much about labels. If you like the shot, then it's OK.
High key is one of those sticking points that those of us in the old guard tend to get worked up about because so, so many people misunderstand it. As I see it, there is text book high key, where you match (key) a light toned background with light toned clothing/accessories and use a low/even lighting ratio etc. The idea is to match the clothing to the background to make the subject's face contrast more within the image.
In modern vernacular, the high key style tends to mean very overexposed.