I found it quite interesting that they did this. Looking at it from one perspective, Ubisoft basically called the bluff of many pirates ("We only pirate because of the eeeeevil DRM")... and judging from a few torrent tracker sites I looked at, the pirates were basically proven to be full of sh*t.
The torrents says only about people who do not buy games, lot of people who refuse to buy securomed games have purchased this game only because it's DRM free, same with Sins of a Solar Empire and lot of games from gog.com... every single software ever released got pirated... be it PC, console or mobile application... and no DRM ever will change that...