This Camaro was decorated with 3D-printed designs by artist Ioan Florea to highlight the intersection of art and technology. 

Last week, I had the opportunity to attend Inside 3D Printing in New York City, the largest stand-alone 3D printing conference in the world. More than 12,000 people attended, which represented a three-fold increase in attendance from the year before.

During the conference, I interviewed 3D printing executives, attended keynote presentations, and walked the exhibition halls. Here's what I learned from the experience.

1. The real money to be made in 3D printing will be from producing 3D-printed parts for final products.
Although 3D printing is most often associated today with being a prototyping technology that allows users to iterate designs quickly and affordably, 3D-printed parts for final products will likely continue to make up an increasingly greater percentage of the overall industry's revenue.

According to Wohlers Associates, 3D-printed parts for final products increased by 66% annually in 2014, nearly double the industry's 35.2% overall growth rate for the year, and they represented about 43% of the industry's total $4.1 billion in worldwide revenue.

Looking ahead, companies in the business of supporting 3D-printed parts that end up inside final products with hardware, services, and materials appear to be in the best position to benefit from this growing opportunity.

2. The way to a venture capitalist's wallet is through a successful Kickstarter campaign.
After attending several keynotes about the venture capitalist's perspective on 3D printing, it became evident that launching crowdfunding campaigns through sites like Kickstarter has become a popular way for start-ups to validate their takes on 3D printing. If a start-up experiences success in the crowdfunding arena, it can attract interest from the VC community -- and also give itself a bargaining chip in negotiating investment terms.

3. HP wants to create a major step-change in 3D printing.
During Hewlett-Packard's (HPQ -2.58%) keynote presentation, the 2D printing giant highlighted that it has tremendous experience with digitizing analog and cumbersome technologies. HP told a story about how it invented a digital printing press that can print as little as one book to tens of thousands of books, without ever wasting a page or skipping a beat. This innovation fundamentally changed the publishing world in terms of inventory management and allowed more books to be kept in print.

Ultimately, HP wants to leverage its experience in creating a step-change in publishing and apply it to creating a step-change in 3D printing, so that the technology captures a greater percentage of its potential addressable market.

According to J. Scott Schiller, worldwide director of HP 3D Printing, there's an order-of-magnitude difference between current 3D printing adoption rates and potential 3D printing adoption rates. In Schiller's view, hundreds of thousands of enterprises could be adopting 3D printing but haven't yet.

The heart of HP's 3D printing vision entails creating a 3D printing technology platform that, over time, becomes faster, produces higher-quality parts, operates at a lower cost, and is highly predictable for engineers. In other words, HP's entrance in late 2016 with a technology it's calling Multi Jet Fusion, which it claims is at least 10 times faster than leading technologies on the market today, is likely only a starting point for the company to make greater advances.

4. The industrial 3D printing segment may not have much mainstream visibility, but it's the most important part of the industry today.
Although the sub-$5,000 consumer 3D printing segment gives 3D printing high visibility and raises awareness of the technology in general, behind the scenes, industrial 3D printers make up the majority of the industry's hardware sales in dollar terms. According to Wohlers Associates, industrial 3D printers priced higher than $5,000 represented about 8% of all 3D printers sold in 2014, but in terms of revenue, it represented nearly 87% of total 3D printer sales worldwide.

5. Metal 3D printing continues to be a high-growth area of the industry.
Wohlers noted that the metal 3D printing industry, in terms of units, grew by 54.7% annually in 2014, and in total, 543 metal 3D printers were shipped throughout the year. This growth suggests that metal 3D printing is becoming more widely accepted as a viable option for one-off and lower-volume manufacturing applications. As manufacturers figure out new applications for metal 3D printing, it's reasonable for investors to expect this trend to continue growing in the years ahead.

6. Material prices will have to come down for adoption rates to increase.
I spoke with various 3D printing industry insiders about a central challenge that's bottlenecking adoption rates across the industry: The price of materials, which can fetch upward of hundreds of dollars per kilogram, can be significantly more expensive (orders of magnitude, in some cases) than similar materials used in conventional manufacturing.

The collective view I gathered is that material costs will eventually have to decrease so 3D printing can become more cost-effective than traditional manufacturing processes. How this could affect 3D Systems' and Stratasys' razor-and-blade models remains an unanswered question for investors.

7. Disruption and innovation can come from anywhere, and this factor is really difficult for investors to account for.
Since the start of this year, there have been two major 3D printing breakthroughs from entirely new entrants. In January, Voxel8 showed off an electronics 3D printing platform, and more recently, Carbon3D unveiled its proprietary CLIP technology that claims to be orders of magnitude faster than any other major technology on the market today.

As a 3D printing investor, the threat and implications of technological disruption from outside competitors is extremely nuanced and difficult to quantify. Staying up to date on the most recent industry developments is the first line of defense in evaluating a potential competitive threat.