I finished it in three days. That being said I put in 14 hours a day for three days.
I liked it but there were a few issues. I liked the story, it was good. The problems I had were this -
1. The bugs. There were multiple bugs. I played it on Xbox and even with the first patch there were plenty of bugs left. If you travel fast to some locaitons after completing some quests it would remove the quest from your list and put it in the DONE category, yet you would not get the XP or items you were supposed to get, or see the related cut scene. Also in a few areas doors were missing the bar they were supposed to have and key plot items just were not there. In those cases you had to quit the game out to the main menu and come back in and try again. Sometimes it took a few tries before the items would appear. There also were bugs with many of the achievements like the one I listed above which keeps anyone who does a full play through from getting all the achievements they normally would have acquired.
2. The level of difficulty. It seems to be made for multiplayer only. You don't see this until Act II, but it starts to get insanely difficult to the point one person has no chance. I didn't die at all in the first Act, then died over 100 times in Act II and almost 200 in Act III. You continually get rushed by swarmed from all angles and there is nothing you can do as one person to stop from dying. Luckily it just puts you back a few feet and takes 10% of your money and lets you try again. I found most hard bits just became a war of attrition, I would kill off three or so foes in one life, die as the other fifteen or so attacked me, and then go back and kill off a few more each time until I was through that section. I found that strategy detracted from the gameplay though. When you reach one of those areas you are just like, oh here we go.
Overall I liked it though. The obviously are making a sequel so hopefully they will iron out the kinks and work on the gameplay for the next one sure.