Does a great first 2 acts make up for a lame final act? *SPOILERS*

For me, this is the age old question as it pertains to horror movies. It seems the downfall of so many horror/thriller/creepy movies is the ability to put a nice bow on it and come up with a strong final act. Vivarium is a great example of this IMO. I was thoroughly riveted and enthralled with the first 80 or so minutes all the while saying "please don't muck up the ending". And.....er...they mucked it up.So when I ask myself if I enjoyed this or not, I'm torn.

Based on the opening scene, I had convinced myself that the ending would be that they were in some sort of a nest being controlled or run by birds. And perhaps that's what they were going for with the final scene. Who the hell knows? There was nothing. I'm all for a vague and mysterious ending to let the viewer determine their ending, but this was left way too ambiguous.

Based on the performances and the creep factor, I'd still recommend it to those who are fans of this genre, but I felt it could have been so much more...