malware stories

As Android zips past iOS as the mobile platform of the masses, it has mirrored Windows' role in the PC-Mac wars in two ways: 1) its open strategy has allowed it to become far more widespread and 2) due to its ubiquity, it has become the target of choice for hackers, criminals, and other assorted nefarious codemonkeys.
Computer viruses are big news. Over the past decade, malware like the ILOVEYOU virus and Stuxnet worm grabbed headlines worldwide, and PC owners are constantly hammered with reminders about antivirus software. But what about smartphones? They're mini computers, after all, and they communicate over more networks than most PCs. Why hasn't there been a major cellphone virus yet?