It's been a long, long time since pinball has been this healthy. I think you have to go back to the early '90s to find a time when pinball manufacturers were so stable and there was an expectation that the next game(s) coming out would be good. In the early 2000s, things were so wildly up and down between releases, and the economy was just as shaky.
I think a huge part of today's resurgence comes from the '70s and '80s arcade brats coming into money as well. I wonder if the '90s kids will keep things rolling and expanding the market or if the '70s and '80s kids will need to be the majority of the market. I would think that people in their 30s to 50s now could be in pinball buying mode for a good decade or two.