San Francisco - Apple (NASD: AAPL) on Wednesday unveiled its long-anticipated tablet computer, the "iPad," at a media event in San Francisco. The device, which will cost between $500 and $830 when it ships in coming months, is a half-inch thin, weighs 1.5 lbs., and sports a 9.7-inch display with virtual keyboard, built-in speakers and microphone. "It looks like, well, a big iPhone, pretty much as anticipated," The New York Times wrote on its live blog of the event.(NYSE: T) Wi-Fi hotspots, Bluetooth and AT&T 3G service, costing $15 for up to 250MB of data per month, to $29 per month for unlimited data. Pricing for the iPad will depend on amount of memory and whether the version supports 3G; a 16GB version without 3G costs $500, while the 3G version will sell for $630.

Apple said the iPad offers 10 hours of battery life, with over a month of standby life.

On the software front, the iPad will ship with a built-in calendar, address book, Maps application, and iTunes Store.

On stage at the event, Apple's CEO Steve Jobs said the App Store now counts 140,000 applications, which have been downloaded 3 billion times.

For the iPad, users can access applications as they would appear on the iPhone, or in automated "pixel-doubled" version that makes the apps run "full screen." The company also said developers will be able to modify their applications to take advantage of the iPad's larger display.

Jobs showed off the how the device's size allows it to more properly display newspaper websites, including Time.com and NYTimes.com, and was joined on stage by Martin Nisenholtz, senior vice president of digital operations for The New York Times Company.

A new iBooks application for the iPad will let users download e-books directly from the iTunes Store in the EPUB format. Apple touted support from publishers including Penguin, HarperCollins, Simon & Schuster, Macmillan and Hachette.

Several of the bloggers covering the event reiterated a potential concern with regard to watching long-form video on a tablet computer: that a user would have to prop the device up on her lap, or else peer down at it resting on a flat surface -- with the alternative being to hold it at an angle for two-plus hours during a movie.

A dock accessory announced appears to serve as a prop for the device; Apple will also a physical keyboard accessory for the iPad, that doubles as a battery charger.

Models without 3G will ship in 60 days, while the 3G models will ship in 90; while pre-orders are not yet available, the company is offering an email notification service.

The device will be available with 16GB, 32GB or 64GB of Flash-based storage. For connectivity, it features free AT&T.