I put a few cents in here. I was taught to use lightwave first (on an Amiga) so it is the standard that I use to compare 3D software. Now my lightwave knowledge is dated a bit (last used version 5.0) but I can tell you why poser isnt used more:
the key framing system is horrible!
Now in lightwave there isnt a keyframe unless I hit "create key" in poser if I move something on frame 11 it is as if I created a key, every time. without more numeric control it is hard to control how things move as well.
those have been my experiances anyway.