GenCon has been growing attendance every year recently, BoardGameGeek has been around for many years, the Dice Tower has been going for years, TableTop is finishing season 3... There are lots of independent publishers, and crowdfunding models have worked their way into small publishers' business models...compare GMT Games' P500 model, for example.
Personally there's some disillusion with the state of D&D, and it's also true that board gaming is simply better now than it was 10 or 20 years ago. There are better games, different types of games, and people have more points of entry.
The industry is microscopic compared to videogames, but it is growing, and I think the sheer quality of modern games will help to sustain that growth.