UPDATE: Check out our Hands on: HP TouchPad review
The HP TouchPad is really important - not because it's a brilliant tablet, although it does look pretty tasty, but because it's yet more proof that the PC era is coming to a close.
The PC isn't dead, and won't be for a long time. But the HP TouchPad is yet another triumph for the planet's fastest-growing operating system, ABW. That's Anything But Windows.
In HP's case its ABW is WebOS; on Android tablets it's Honeycomb; on the BlackBerry PlayBook it's BlackBerry Tablet OS; and on iPads it's iOS.
The devices differ and so do their operating systems, but the one thing they all have in common is that they're not running Windows. Many of them don't have Intel inside, either. They've got Snapdragons or Tegras or A4s or whatever particular flavour of ARM processing the manufacturers have chosen.
If I were the sort of person who used the phrase "paradigm shift", I'd use it here. What's happening is incredible, and it's happening incredibly quickly. Until very recently, personal computing generally meant Windows running on Intel, with a smattering of AMD, Linux and Mac OS X to keep the internet in arguments. Now, though, personal computing often doesn't involve traditional computers at all.
Power in your pocket
This is classic end-of-empire stuff. Mobile devices are doing to the PC what the PC did to the mainframe, what rock and roll did to big bands and what blogs did to newspapers, and in years to come they in turn will be shaken up by a whole new way of doing things.
The future fits in a pocket - a really big pocket in the case of the iPad, but a pocket nonetheless. Fancy some numbers? Here are some really amazing ones: according to IDC, 92.1 million computers were shipped in the fourth quarter of 2010 - but smartphones did 100.9 million. Factor in tablets, which IDC reckons will hit 70.8 million by 2012, and you can see which way the technological winds are blowing.
Those numbers will only become more dramatic. The PC market is a mature one, but smartphones and tablets are young, exciting and fast-moving.
That means we'll get saddled with some right crap - every tech bandwagon produces its share of clunkers as panicking firms desperately try to clamber aboard, and it's much harder to make a good mobile device than it is to make a video render of something that looks like a good mobile device - but that won't change the bigger picture.
Technology has advanced to the point where personal computing isn't necessarily something you need a PC for.