The number and rate at which people are choosing 10+ is almost frightening. However, it's definitely predictable - as well as comforting to know that we are not alone.
jasonshen brings up a good point by saying that the data will be biased towards the people who check HN more often. This is true and, while I don't expect this to be a formal, or even accurate, poll in any way whatsoever, it seems as if it has reached the front page - which may help. For example, if this stays there a little longer, we'll have a better idea of the number of people who check 10+ times a day in comparison to those who check 1-5.