Apple says it had sold upwards of 300,000 of its newfangled $499-$699 Wi-Fi-only iPads by Saturday midnight, the widget’s first day out, around half what some people thought but on par with the iPhone.

The number includes pre-orders and the Wall Street Journal says the stores didn’t sell out.

The new iPad owners, reportedly mostly the Apple faithful who already own Macs and iPods, immediately downloaded a million+ applications and some 250,000-odd eBooks (Apple now has a 60,000-strong eBook store called iBooks of course).

Financial analysts reckon Apple, which has just set a series of all-time highs on the stock market with even better days forecast, could move about five million of the things by this time next year.

iSupply is “conservatively” thinking 7.1 million; Forrester three million.

Steve Jobs claims the dingus is a “game changer” with implications for publishing, but then he hasn’t offered any numerical forecasts.

Other people are fretting over the fact that netbooks sales are slowing and relate it to the advent of the iPod; HP, Dell and Acer wouldn’t talk to BusinessWeek about their netbook inventories and Intel wouldn’t talk about about the order rate for Atoms.

As a sign it has arrived, the iPad is already being sued in separate patent infringement suits lodged by EMG Technology and Elan Microelectronics.

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