RIMM), whose BlackPad tablet device will reportedly hit the market this fall, and there's been whispers of tablets arriving soon from Motorola ( MOT), Dell ( DELL) and even Hewlett-Packard ( HPQ). But like Apple's plunge into tablets with the iPad, the entrants, led by Cisco -- the early favorite to conquer the business market -- face the question: What will people do with business tablets? For Cisco, which supplies network equipment and pushes expensive teleconferencing services, the key is to spark video calling. "They are trying to bring video into the mainstream," said Jeff Heibert, CEO of ROI Networks, an office communications company in San Juan Capistrano, Calif. "And Cisco knows that if they can make it fun, compelling and effective they will benefit by selling more network infrastructure." One big difference from the consumer tablet trend is that Apple won't necessarily be the frontrunner in the business tablet invasion. Sure, Apple's unopposed iPad campaign has not only redefined the tablet category, it has given Apple an astoundingly hot new growth product and a one-year lead on the competition. But while Apple has employed a deft hand in the consumer market, it has come up all thumbs in the business sector. For example, after three years, the Apple iPhone is still a rarity to IT managers, and the iPad, while a fun new toy for some office gadget fans, still sits outside the corporate firewall. The office is largely RIM's domain and BlackBerries are still the champion of work phones. And as RIM presence grew, players like Microsoft ( MSFT) and Palm have vanished. Meanwhile, with the arrival of HTC's Verizon ( VZ) Incredible and Sprint's ( S) EVOs as well as Motorola's Droid phones, Google's Android operating system has been able to worm its way in to the enterprise arena. Cisco, on the other hand, has had no hand in the phone action, but its entry into the tablet market is particularly intriguing. Cisco's choice of Google Android software to run the Cius is a brilliant move to go with something popular, nimble and open, giving the effort little baggage and lots of runway. In a perfect Cisco world, the Cius would be another data-hungry device that would force companies to buy more Cisco infrastructure. Here's what the tablet players bring to the office.