Cardboard games need to be turbocharged by the internet. It's clear to me that the massive success of Eurogames in the last couple of years is based on two factors. One, they are awesome games. Two, people are telling lots of other people about them on boards like gamegeek, game blogs, and other online forums.
I think the "Next Big Thing" in traditional gaming will be a seamlessly integrated internet & traditional game. Maybe a TCG, maybe a wargame, maybe something else. That doesn't matter. What does matter is the internet allows remote players to be part of a global community. If joining that community also provided additional gaming resourses that specifically enhanced a particular game, that game would have a leg up on all the other 'unplugged' games. I actually submitted this example to Wizards of the Coast when I worked there. I got a lot of smiles and nods.
Imagine a wargame, a cross between Axis & Allies and Warhammer. The base sets contains a healthy supply of game pieces and a small supply of maps designed to be laid out in an assortment of configurations. The game comes with one scenario, complete with pre-built army lists for all sides. Sounds like every wargame ever made, right?
Now, what if registration on the website provided you access to both an army builder, allowing you to easily create different armies based on personal tastes AND build scenarios based on how you liked to play. Your new army lists would print out with the touch of a button and the scenarios could be shared, rated, and the best ones made OFFICIAL by the publisher.
Take it a step farther. Game balance is always an issue with wargame army lists. What if you imposed an economy where the more a specific unit was used, the more points it cost. Units that weren't used would reduce in cost. The game would balance itself. New units could be introduced regularly with minimal playtesting because their correct value would take care of themselves by the system.
The game itself would still be played on a table between friends, just like any other wargame, but each game would impact an entire worldwide community.
I would play that game.