The first reviews of Apple Inc’s hotly anticipated iPad tablet computer hit the web on Wednesday night, ranging from the ecstatic to the ambivalent.

The iPad goes on sale in the United States on Saturday. Apple has touted the device as inventing a new class of computer between a laptop and smartphone.

Tech guru Walt Mossberg of The Wall Street Journal agreed that the iPad could change the nature of computing. “After spending hours and hours with it, I believe this beautiful new touch-screen device from Apple has the potential to change portable computing profoundly and to challenge the primacy of the laptop,” he wrote. “It could even help, eventually, to propel the finger-driven, multi-touch user interface ahead of the mouse-driven interface that has prevailed for decades.” he added. However, he noted many drawbacks of the device. “The iPad lacks some of the features such as a physical keyboard, a webcam, USB ports and multitasking that most laptop or netbook users have come to expect.”

The New York Times’ David Pogue was less enthusiastic, castigating the device’s “horrible” touch-screen keyboard, its incompatibility with Flash videos and its inability to multitask.But while he said the device was unsuitable for techies, he recommended it for other people, noting that although it was basically a gigantic iPod Touch, “the simple act of making the multi-touch screen bigger changes the whole experience. Maps become real maps, like the paper ones. You see your e-mail inbox and the open message simultaneously.”

“The iPad is so fast and light, the multi-touch screen so bright and responsive, the software so easy to navigate, that it really does qualify as a new category of gadget,” he wrote. “Some have suggested that it might make a good goof-proof computer for technophobes, the aged and the young; they’re absolutely right.” he added.

PC magazine also noted the device’s drawbacks but praised it as a “gorgeous, slim slate with a beautiful touch screen” and called the iPad a “winner that will undoubtedly be a driving force in shaping the emerging tablet landscape.”

“Apple has pretty much nailed it with this first iPad though there’s certainly room for improvement,” wrote Ed Baig in USA Today.

Nearly three years after making a splash with the iPhone, Apple has delivered another impressive product that largely lives up to the hype.