I haven't played with iclone. The short answer is that Daz/Poser are programs for posing stills from pre-made models. Maya, 3DS, Blender and several others, are basically a group of programs all squeezed into one, meant for doing from beginning to end animation and movie/tv fx work.

It's more complicated, because Daz and Poser added animation stuff quite a while ago. They aren't as full featured as the others, but I've seen some really good work done with them. There are some basic modeling tools, but they are extremely basic and in most cases not of much use. When you get into the animation/fx softwares there are still things they don't do or don't do well. You will almost for sure want a 2D software like Photoshop or Gimp. A large number of people use external modeling programs. There are also external motion/animation programs that get used. Then you get into render engines and people are all over the place about what internal or external one to use.

In short, I have used 3DS, Max, and Lightwave to do animations, where I used no other program and no work done by other people. I've played with Blender enough that I think I could also do that in Blender. You realistically need stuff done by others to use Daz/Poser. But realistically it's unlikely you would use just one program and nothing from any one else, even if you are using Maya, 3DS, or Blender. ZBrush is used a lot for modeling and texturing, so are several others, including a lot of cad programs. Lip sync tends to be done a lot with external programs. Motion capture is a huge thing and is most often done by an external program. People use what ever seems to work well for them. You don't have to lock your self into one niche with one piece of software.

Daz and Blender are free, so they are a good place to take a first look. If your main interest is animation, then there are tons of free models to play with and you can exchange those between programs (with a bit of work). At some point you will want to adjust some models. You can only do that to a limited degree with Daz and Poser. The limit is a lot more then you would first guess, but it is limited to the morphs available and what you can do with some deforming tools.