Ubisoft has decided to give Assassins Creed Unity free for a week on PC. They are also donating 500,000 for the reconstruction of Notre Dame Cathedral which was destroyed in a fire recently.
After this goodwill gesture by Ubisoft, there seems to be an outpouring of support by the community and this is seen with the surge in positive reviews for Assassins Creed Unity on Steam.
Source: N4G PC Assassin's Creed Unity Starts To Get "Very Positive" Reviews After Going Free For A Week