The new iPad goes on sale at Apple stores across the United States on Friday as the gadget-maker seeks to stay a step ahead of its rivals in the booming market for sleek touchscreen tablet computers.
Apple will be taking online orders for the iPad 2, which was unveiled by chief executive Steve Jobs last week, beginning at 4:00 am (0900 GMT) and the device will be available in the company's 236 US stores starting at 5:00 pm (2200 GMT).
The iPad 2, which is one-third thinner, nearly 15 percent lighter and faster than the model released last April, will go on sale in another two dozen countries on March 25.
Besides the size and weight, the other major improvement to the new iPad is the addition of front- and rear-facing cameras that allow users to take still pictures and video and hold video conversations.
Apple sold 15 million iPads last year, bringing in $10 billion in new revenue and creating an entirely new category of consumer electronics devices.
Dozens of other companies have been scrambling since then to bring their own touchscreen tablets to market, most of them relying on Google's Android software to power the machines.
But with the exception of the Galaxy Tab from South Korea's Samsung, rival tablet-makers have enjoyed little success.
Technology research firm Gartner is forecasting sales of 55 million tablet computers worldwide this year and another research firm, Forrester, said Apple has little to worry about for now.
"Competing tablets to the iPad are poised to fail, which is why we're forecasting that Apple will have at least 80 percent share of the US consumer tablet market in 2011," Forrester said.
The iPad 2 arrives in US stores to mostly glowing reviews from the influential technology columnists of The Wall Street Journal and The New York Times.
"While it's evolutionary rather than revolutionary like the first model, the changes Apple has made are generally pleasing and positive, and the device worked very well for me," the Journal's Walter Mossberg said.
Mossberg said the iPad 2 "keeps Apple ahead in the tablet race, at least for now." But he was critical of the quality of the photos taken by its still cameras and its inability to play Adobe Flash video.
"This is a deliberate decision by Apple, and puts its devices at a disadvantage for some users when compared with Android tablets, which can play Flash, or say they will soon, albeit not always well," Mossberg said.
While pleased with the iPad 2 overall, Mossberg said it was not a must buy for owners of the old model.
"Unless you are desperate for the cameras or feel you are laboring under the greater bulk of the original model, I don't advise that iPad owners race to get the new version," he said.
David Pogue of the Times said the improvement in thinness, weight and speed "transforms the experience" of using an iPad and the cameras are a "treat."
"The entire screen is your viewfinder," he said.
Pogue also noted the iPad 2's inability to play Flash video but said the device "will still dominate the market, because it dominates in all the most important criteria: thinness, weight, integration, beauty - and apps."
More than 65,000 applications have been created for the iPad, while there are currently only about 100 crafted for tablets running Google's Android operating system.
Pogue said another factor likely to keep Apple on top is the fact that the iPad 2 costs less than the Samsung Galaxy Tab and Motorola's new Xoom.
Apple is selling the iPad 2 at the same prices as the original iPad, ranging from $499 for the basic 16-gigabyte version to $829 for the top-of-the-line 64-GB model.
The iPad 2 will be available on March 25 in Australia, Austria, Belgium, Britain, Canada, the Czech Republic, Denmark, Finland, France, Germany, Greece, Hungary, Iceland, Ireland, Italy, Japan, Luxembourg, Mexico, the Netherlands, New Zealand, Norway, Poland, Portugal, Spain, Sweden and Switzerland.