Talking of unexplored territory, we’re in a week where we’ll take several more steps into what Apple likes to call the PostPC era. The days when the computer was the main – and only – device that people used to access computing power are numbered, if not finished. The traditional computer is being flanked, by mobiles on one side and tablets on the other. This week we’ll see announcements from Google, Apple and Microsoft that will all stake their claim on this new, barely explored landscape.

Apple went first, and like the 100lb gorilla that they are in this space, threw a whole load of new things at us: updated software, radically redesigned Macs – and two new iPads.

The launch of the 4th generation iPad was a surprise. Everyone was lulled into the rhythm of roughly yearly updates to the device, and to put out another major version just six months after the last…? That’s aggressive – and has probably caught many of its competitors on the hop. But then, a space which Apple had to themselves for a year or so is rapidly getting very, very competitive.

Hence the day’s big announcement: the iPad Mini (seen in all its slightly smaller glory above). The market for a smaller, single hand tablet has been growing without Apple playing in it. There’s Amazon’s tablet storefront, the Kindle Fire, and Google’s Nexus 7, a lovely little Android tablet which I’ve had for a couple of months now, and had to hide from my wife, who rather fancies it. The iPad, you see, is just too big for her to hold comfortably for any length of time, while the Nexus 7 suits her perfectly.

It’s just possible that she’ll find an iPad Mini under her Christmas tree, though. (She doesn’t read this blog, I’m not blowing any surprises… :-) ) It’s a classic move by Apple to extend the range to a new group of people, for whom the iPad is just too big to use routinely. Children are another obvious group – the cheaper price and small size might make it a perfect device to extend Apple’s growing presence in schools with the iPad, particularly for primary school children. We’ve seen the company do this before – the iPod range extended downwards with the iPod Mini, then the iPod Nano and the iPod shuffle, before reinventing itself as the iPod Touch.

As the iPad line starts to expand in a similar manner – and a similar range of competitor devices grows – we’ll start to discover what an ubiquity of such devices means to the way we consume and create information. Already the commuter sat on a train with his chuck laptop is beginning to seem rather, well, quaint compared to the sea of people using iPads and Kindles around him. This is only going to speed the change. And it’s clearly a change which speeds us towards unknown territory.

The iPad Mini is, in effect, a scaled down iPad 2, with a few borrowed features from the two newer generations of iPad. But its impact, I suspect, is likely to be much larger than that implies.