I use Poser to create animated instructional videos. The results are quite satisfactory. While Poser is a low-budget program, it is capable of very fine results. It all depends on how well you understand what the program is capable of and how much time you're willing to invest. You won't create Pixar or ILM quality images but I've seen professionally made, theatrically released animated films whose image quality and animation was clearly inferior to what Poser can deliver. I don't see why Poser couldn't be used to create a "real" movie.

"Facts are the enemy of truth."