Traditionally game consoles have been walled gardens, where users could wander freely amongst the delights of the games provided. You were never allowed to play with gamers who dwelt in other gardens – in fact, you couldn’t even see them or be made aware of their existence. Now, that reality is changing.

We’re seeing glimmers of this on Nintendo Wii U. Australian indie developers Nnooo are releasing Cubemen 2 later this year on the Wii U, joining the PC and iOS versions in allowing cross-platform multiplayer and sharing of content.

“I’m really proud to be able to announce this,” said Nic Watt, creative director at Nnooo. “We’ve spent the last few months working with both Nintendo and 3 Sprockets, the game’s developer, to make this a reality. Cubemen 2 is an amazing game and a great fit for Nintendo players. We can’t wait to see how creative they are, whether in tactical multiplayer online or in the new levels they build.”

There are 4,000 user-created levels available, which Wii U users can access. The game is playable across the Wii U, PC and iOS.

This is newsworthy because it’s so rare. World of Tanks on the Xbox 360 has its own servers, and there will not be cross-platform play with World of Tanks on the PC. Certainly Wargaming would love to see that happen. Activision would be happy if Call of Duty players on Xbox could play with PlayStation players; likewise EA would be excited to have FIFA players competing across all platforms. Yet the console makers generally don’t allow this.

Uniqueness is one of the key selling points of consoles. Exclusive titles sell hardware, and that’s been true for decades. If you really want to play a particular title that’s only the PS3, that’s why you’ll choose a PS3 over an Xbox 360. Hardware makers want to have exclusive titles in order to sell hardware… yet an exclusive title is limiting the audience by its very nature. Yes, Halo sells Xboxes. But Halo could sell many more units if it was also available on PlayStation. If the profits in the business are really from software sales and not from hardware, is this limiting potential profitability

Look at it another way. Xbox Live has some 50 million members, PlayStation Network over 90 million members. Those are impressive numbers… until you start looking at the size of other networks. World of Tanks has 60 million members. Apple’s Game Center has over 65 million members. Zynga has 187 million monthly active users. Facebook has over 1 billion members.

The potential audience for gaming is far larger than any one network – well, maybe not larger than Facebook’s network, but certainly larger than any console’s network. The power of gaming platforms is rising, making it easier for games to be cross-platform (especially more casual games). The vast majority of the gaming audience would prefer that a game is available on multiple platforms.

Second-screen gaming is a way to keep players involved in a game when they aren’t able to get to their console. Publishers want people to engage deeply with game brands, and that means making the game available to the player wherever and whenever possible. Allowing players to use a tablet or a smartphone to check into a game may not be full cross-platform gaming, but it’s still time spent with your game and not some other game.

King has had a huge hit with Candy Crush Saga, partly because the game is playable on multiple platforms – and your progress is synced across those platforms. Play on your phone in the morning, then grab a session on your lunch break via Facebook on your computer, then play on your tablet when you get home – and your progress is saved and tracked through each platform, so you never have to repeat a level unless you want to.The trend is obvious – more and more, games are allowing cross-platform communication at a minimum. Asynchronous play is relatively easy and undemanding compared to synchronous multiplayer, so that is already being done. The difficult feat is to take a game like Call of Duty and make it playable seamlessly across consoles. Activision would solve that problem handily if given the chance by the platform makers.

What may in fact happen ultimately is that the console market will look more like the mobile market, with hardware makers generating profits through sales of hardware and a cut of all software sales. Hardware pricing is kept low for consumers by network providers that subsidize the hardware in order to lock in subscribers for two years. There have been rumors of such an arrangement for the Xbox One, which would reduce the hardware price if you sign a contract for Internet service with a provider like Comcast.

Game publishers will continue to push for more cross-platform game play and connectivity, while platform makers will continue to resist. It might be a big competitive advantage if your console offered cross-platform gaming… or by reducing the value of exclusives it might give your competition a boost. No one knows, so there is great reluctance to be the first to try it out. What we’re likely to see are more careful moves in that direction with continued gauging of consumer response. Console makers will need to decide, ultimately, where the profits are located in the overall business and optimize the business for that. The equation is different now than it was in times past, and the variables are changing.

You can bet that Wargaming will continue to argue for connecting World of Tanks on the Xbox 360 to the World of Tanks audience on PC. A bigger audience will make all the players happier, because there will be more people to play against. And you needn’t worry if your friend has the right hardware to play a game. Hardware is becoming less important, and the game and its network of players is becoming more important. Game makers, platform holders and marketers are all adjusting to this, some more rapidly than others. It’s happening, and the only question is how each company adapts to it.