In the original article they mention that it shipped 3 million but they assume that at least half of that is sitting on the shelves still:
It's clear that Take-Two Interactive, parent company of Rockstar, was betting big on Max Payne 3's success. In its last financial report, Take-Two claims retail sell-in of about 3 million units. With only 440K units sold in the US, that means there are a few million units of unsold inventory sitting on store shelves. If you haven't bought Max Payne 3 yet (and by the looks of these numbers, you likely haven't), retail markdowns are likely to happen in the coming weeks.