I agree with Smiley, we're at the end of First Innovation. Consider, while there's a new breakthrough in regards to 3D printing almost daily, the vast majority of them are announcements of plans to start funding for a business to get an idea to market, rather than actual announcements of products being released into the market.

Perhaps the biggest thing about 3D printing as a technology is the amount of media coverage of early development. Other big technological fields have been in the hands of big secretive orginazations whose only milestones to the public were final products arriving in stores. The common belief in business has been for a long time that the public will turn sour at seeing the messy process of product development, and won't be as wowed by the finished product if they've had years to know it was on the way. With the majority of these small 3D printing start-ups, we see the general mess that is development and we relate to it in a more human way. When the product comes to market, it already has followers who feel like they already know much better how it works because they saw it grow from an idea up.

Another major design challenge that Smiley didn't mention is in the materials themselves. There's a race on to invent a significantly electrically conductive thermoplastic suitable for FFF.