Of the tablets on view at CES, devices from Motorola and Research in Motion were standouts.

There is undoubtedly an opportunity for other tablets, particularly with different screen sizes and in the corporate market, where Apple has not traditionally been very successful. And the sheer ubiquity of tablets based on Google’s Android software makes that the platform that Apple cannot ignore. The tablet segment is expected to more than triple to 50 million units in 2011, with Apple seen as by far the dominant vendor. Despite Apple’s big head start, no one expects its competitors to stay away. Sony Corp said it hopes to become the world’s second-largest vendor of tablet devices by 2012, but failed to show anything.
Dell consumer marketing head Paul-Henri Ferrand, said: “Apple can’t expect to have the tablet market to itself.”

A host of manufacturers are producing tablets based on Android, which is free to license. But Android tablets will face the added challenge of not only competing against the iPad, but also one another.

Lenovo, LG Electronics and Asustek Computer were just a few of the companies showing off Android tablets at CES. Some tablet makers await the next version of Android, known as Honeycomb, expected in the next few months, before moving ahead.

Microsoft’s Windows software is cropping up on a few tablets, but it is not well-suited for the devices.

Tablets from RIM and Hewlett-Packard will be closely watched precisely because they do not use Android, and may be able to offer users an experience they cannot get elsewhere.

RIM’s 7-inch PlayBook tablet, set to launch in February or March, received positive early reviews after the company offered hands-on demos at CES.