Yeah, too hard to say. Leading the way I think is Statasys. They have been doing this for so long now (decades) who knows what tech they are working on, what they can do today blows me away, so who can tell what they have up their sleeve. My money's on them.

HP are doing their usual thing, they will target the engineering field first with a big industrial type machine at a reasonable price and then ooze into the home with something small and even cheaper. I'm not knocking HP however, they do make good hardware that is pretty well known for way outlasting it's expected lifespan.