you gotta have Acrobat 7 "pro" or better...I use Acrobat 8 pro($450 or $150 updrade from std version)
All you do in Acrobat is select the "3dtool" and draw a box. then it asks you for the location of the u3d file, and that's about it.
I don't have Poser, so I can't comment. But Daz is a good Free Solution... thats the only reason I have it installed.
I was really hoping that C6.1 would have added the .u3d format
I agree with you about Freehand, I really hated to move over to Illustrator. Macromedia was a very good company