"There's really two separate sections of the market," says McKinney. "Coming down from the desktop to the notebook to the netbook it's really about 'what is the right level of mobility?'.
"The slate is Windows 7 so it's coming from that end; what's the next thing beyond the netbook that gives me portability, access usability… the smartbook is coming from the other side, from phones, and it's a step up.
"A smartbook is primarily in the cloud, it's primarily about connectivity, I'm not really running local apps, I'm running widgets that access my information in the cloud versus a netbook with Windows 7, x86 and I'm running client apps.
"The difference being that with a netbook I'm going to get four hours of battery life and with a smartbook I'm going to get 20 hours of battery life - and it acts like a phone. I can have all my apps running, I get the advantage of all the Android apps, it's always on – I don't have any boot time so I open the lid, boom it's running.
"Think of it as a phone – but your iPhone doesn't last 20 hours, your Google Android phone doesn't last for 20 hours. I've this dinky little ARM processor and I've got all this space; you can put a big honking battery in.
"The trade-off is weight so you can't go crazy with it. But for the first time you can create a device that's always connected – particularly for those people who are cloud based; you've got your Gmail account and your calendars online…"
The slate is all about content consumption, rather than being a general-purpose computer, explains McKinney; "Touch is not the universal solution for everybody, it's not going to replace the keyboard, it's not going to replace other kinds of interfaces".
And no, it's not an attempt to rush something out to cash in on the Apple hype. "This isn't a reaction to 'oh my God, the fruit company's doing something, hurry up and let's do something'. We started the work on this five years ago."
In fact the slate goes back to an ereader prototype that HP Labs produced, with a touch strip for scrolling; the feedback from users was that they didn't want a device that only did one thing – they wanted to be able to write on the screen and they wanted to play video. "You've got all this great content and it's not just text; it's imagery, it's video, it's audio. Look at Hulu and the whole role of video in peoples' lives now," says McKinney; "the world is a rich media world and people don't want a device that cuts out half the world."
The colour screen you need for that meant e-ink was out the of the question (McKinney says he's stopped waiting for the promised colour e-ink screens), although he confirms that HP is working with Conde Nast and other publishing companies on creating content for the slate.
Time and tablets
So why is the slate coming out this year? "There's a couple of things that have happened," McKinney claims. "One is Moore's Law getting down to a price point; delivering a $5,000 device is not very useful. The available technology of touch: the technology guys like NTrig have built touch mechanisms I can put on to those kind of platforms.
"Operating systems: Windows 7. It's all coming together and converging. We've been out there for almost three years, really evangelising touch, getting the message out there that touch is useful. You can look back and see all the pieces; touch and tablet computing and wireless connectivity, and battery improvements, getting to the right price point, the right mix just at the right time. From my perspective, the difference between a good idea and great idea is timing."
Talking of HP's heritage in slate computing, there could be good news for fans of HP's original tablet PC and of what we consider to be the very first netbook, the flash-based OmniBook 300, which had a mouse on an extending stick.
"The TC1100 and the OmniBook 300 are the most popular products we get requests for," McKinney told us, as he does every time we mention them – but this time he added, "And we listen to our customers".
Smartbook is a registered trademark of Smartbook AG, but in this interview McKinney uses smartbook as a generic term for a device which falls between smartphone and netbook
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