In Telephia's latest rankings of the top 10 highest-grossing games in the U.S., two titles stand out: “The Sims 2,” published by Electronic Arts, and “World Poker Tour — Texas Hold 'Em,” published by Hands-On Mobile. What's peculiar about these games is not their content or popularity — “The Sims” franchise has been an enormous success in the PC world, and poker titles are selling like gangbusters — but rather that both games contain significant elements that utilize the wireless network.

Mobile gaming has lived up to its promises of mobility and portability, but until recently, it has been anything but wireless. The mobile data networks in which carriers have invested billions of dollars have served merely as delivery mechanisms, and use of the network connection after the initial download of the game has been negligible. But there are signs of that changing.

“The Sims” is not a multi-player game, but after installation, it uses the network connection for several components of the game. In “The Sims,” a player creates a character he or she controls through daily aspects of life, tending to its food and health needs, career advancement and even friendships and romance. Although the game engine and basic graphical data are stored on the phone, the game reaches out through the network for much of the content itself and allows the player to interact with servers and other players in the community. Meanwhile, “World Poker Tour” can initiate multi-player contests over the network, allowing players to pit their bluffing skills against real people instead of against programming code.

An ever-increasing amount of mobile games are being shipped with a mobile component. While most games now have some kind of a simple leader board component that allows players to match their scores against other players worldwide, many games are in the works with increasingly complicated network components — from the ability to create multiplayer match-ups and swap messages to network-based play where new elements are downloaded from servers through the wireless connection.

However, despite an increasing number of games that tap into the network or offer multi-player modes, the number of people taking advantage of them is still small. Mobile gaming itself is still a niche market, according to wireless research firm Telephia — only 6% of the wireless subscriber base has ever paid for and downloaded a game. And of those roughly 12 million game players, only 8% said that multi-player or network connectivity was important to them, said Jerry Rocha, senior director of mobile content and media for Telephia. Even though many of the online features may be appealing to customers, most customers aren't even aware they exist, he said.

That, too, may change, however, as a few game publishers are now looking to bring the network to the forefront of game play instead of using it to augment it. This summer, Walt Disney Internet Group launched a mobile multi-player game based on its summer blockbuster “Pirates of the Caribbean: Dead Man's Chest.” Unlike other titles on the market, “Pirates” has no single-player option; it's entirely a network-based game, which matches, in ship warfare, up to 16 players against one another on a gaming server. By incorporating delay into the game, “Pirates” allows individual players to react seemingly instantaneously to cannon fire or movements by other players across the network.

Verizon Wireless is the only carrier to sell the game so far, giving it limited exposure in the U.S. But WDIG Executive Vice President Larry Shapiro said Disney will get the game to Cingular and Sprint shortly. Right now, Disney is watching how the game performs among its initial early-adopter hard-core gamers. As the game gains momentum and other carriers begin selling the title, Disney hopes a broader circle of customers will embrace it, setting the stage for future multi-player games, he said.

“We never anticipated this would become an overnight success,” Shapiro said. “This is a new kind of experience. It takes a while for it to get off the ground. … But we're pretty confident we have something here, and there's time to allow it to grow.”

There are advantages for both operators and publishers in creating a network game. The lifecycle of games has become increasingly short as publishers move more games onto the market. With room on carriers' decks to highlight a few dozen games, a new game can fall into obscurity in a matter of months. A networked game can extend the lifespan of a game, perhaps indefinitely, by providing an endless source of new competition, in the case of a multi-player game, or by constantly refreshing content and game play with new game maps and capabilities uploaded from the network.

For carriers, networked games simply generate more data traffic — and hopefully more data revenues — helping justify their investments in 3G networks. A networked game can drive people to a data subscription, such as Verizon Wireless's Vcast or Sprint's Vision service, in order to handle the stream of network traffic on the phone. In addition, the games by definition become subscription games, with customers paying a monthly license fee instead of buying a one-time download license.

The potential for increased revenues are high, so carriers may have to readjust their pricing models for networked gaming to take off, said Telephia's Rocha. A subscription to a game like “The Sims 2” can cost $5 per month in addition to monthly charges ranging from $10 to $20 for a data plan. Some carriers will charge for data by the bit, but as games like Disney's “Pirates” become more robust, minutes and megabytes can add up.

“A heavy user could easily rack up a data bill of $120,” Rocha said. “Eventually, you're going to have to find a way to combine the service with the application. Follow the cable model. You aren't being charged for the access; you're being charged for the programming.”

There's already evidence the industry is willing to swing in that direction. Verizon Wireless just announced it is untethering Vcast music from the Vcast service, giving all customers access to its online music store. Such models could apply to gaming also, where a stiffer monthly subscription fee per game could offset all other usage charges.

Another area the industry is exploring is that of micro-payments, which gives further life to the download model. Publisher Namco just released a version of its popular “Galaga” game, which allows a player to compete in “dual starfighter mode,” a popular feature of the old arcade game, which allows a player to control two spaceships simultaneously. The catch, a 25¢ charge is added to your bill every time you start a game with the feature enabled. Although the additional starfighter isn't downloaded from the network per se, it's easy to see how additional features could be added to a game over time through micro-payments.

Network gaming is starting to attract the interest of a whole other section of the mobile industry. Companies such as Exit Game and SNAP — now owned by Nokia — emerged to create network gaming engines and servers that will host the multi-player combat, message boards and trading forums that this new breed of titles will require.

One additional company has taken a keen interest in the space: Microsoft, which little more than six years ago created a massive gaming business from scratch with the introduction of the Xbox. Microsoft also brought broadband network gaming to the console through Xbox Live a few years later. Now the software giant has its sights set on the mobile community.

At E3 last spring, Microsoft unveiled Live Anywhere, which is positioned to bridge mobile and wireline broadband as well as link the phone, the PC and the Xbox. The portal, which is still in the development phase, now is designed to bridge what Microsoft sees as an extreme fragmentation in mobile gaming, said Chris Early, studio manager for Microsoft casual games. Mobile games remain isolated not only from one another but from their counterparts on the PC and console sides. For instance, instead of creating a scaled-down version of an Xbox motor sports racing game for the phone, a publisher could create a car customization component, “a garage,” where customers can optimize their cars from their phones and then race them when they get to their Xbox at home, Early said.

“Live Anywhere as a vision overall is about connecting gamers with their friends and their games on whatever platform is in front of them at the time,” Early said. “People don't want to be part of a fragmented community.”

TOP MOBILE GAME TITLES BY REVENUE SHARE (U.S.)

While simple puzzle and arcade games like “Tetris” and “Pac-Man” still top the mobile game charts, games with significant network and multi-player components are eking their way into the rankings.