It's begun. Or perhaps it would be more accurate to say it began back in June, when EA released the iPhone version of the Sims concurrently with the PC release. The trend EA started is only going to continue. The linked Reuters article states that several major game developers, including Electronic Arts, ID Software, and Konami, are taking an increased interest in the smartphone as a gaming platform.

And why wouldn't they? Apple's sold more than 40 million iPhones and iPod Touches, that's enough to make a very sizable block of potential gamers. And that block is only going to grow. People are doing an increasing amount of their browsing on their smartphones. The big developers know that time spent browsing could just as easily be time spent buying and playing their products.

Right now major manufacturers are hampered somewhat by the system constraints of most smartphones, but that's changing fast. The iPhone could end up with a dual core processor soon. That would greatly increase the freedom developers would have when designing games.

Most games we see for the iPhone and other smartphones will probably always be relatively simple, cheap app games like the ones we're accustomed to now. But EA has shown with the Sims that a mainstream title can be successfully sold as a game app. With that in mind, I don't think it will be too long until we see an MMORPG get a concurrent release for both mobile and PC use. Knowing Blizzard's knack for increasing their user base, I expect WoW to be the first game to make the jump over to the mobile world. Once they do it, other companies won't be far behind.