Convincing argument that it really is different this time round, compared to the days of “pen computing” and windows tablet edition at the start of the decade.

Microsoft always loved the stylus, but most people hate it. Apple and others understood that actually touching the screen is far more appealing than using some funky pen. And touch requires an entirely different user interface, which Microsoft was unwilling or unable to build into Windows until Windows 7. The casual observer might believe that the usability difference between pen and touch is small. But using a pen is an unnatural act, one that until very recently only a tiny minority of people ever engaged in. The psychological payoffs for using a pen on paper are the tactile feel of the paper, the instant feedback of the trail of ink and the physicality of stacks and files and binders of paper notes. Pen-based computer systems don't offer any of those payoffs.

Touch is one of seven reasons cited. Others include the rise of e-readers, HD video on demand, app stores, and mobile-specific operating systems like Android.

A further reason would be improvements in soft keyboard technologies. That a soft keyboard could work, as on the iPhone, was a surprise to many; we probably won’t see those funky projected keyboards taking off any time soon. While some will say the tablets aren’t for performing serious work, everyone needs to type occasionally, at least to perform a web search.

Another reason is battery improvements, though we’re still a long way off from being able to play HD video, surf the web, and chat on skype, simultaneously and all day long.

Great, now we have all the reasons in the world. Unfortunately, we don’t have the CrunchPad anymore and the Apple rumour is just that. Will tablets really take off? For all the arguments, there remain some unanswered questions.

Most important, the form factor; although lighter and thinner than ever, they are still awkward to hold, maybe awkward enough for only geeks to love and certain professionals to tolerate. This is an area where Apple surprise us just as they did with the MagSafe power adaptor. It was innovative, unexpected, useful, intuitive, and a product of the physical world rather than the digital world. They’ll do well to repeat that feat with some kind of stand for the rumoured tablet.

The other thing is connectivity. I can’t see these taking off in a big way unless they ship with a 3G sim card, like the Kindle. We’re finally entering an era of more SIM cards than people and it makes a whole lot of sense - at least among retail consumers - to treat bandwidth like oxygen, instead of having to bash wifi into working for us. It’s true that wifi itself works well these days - the client detects the type of encryption and asks for a password. The problem comes when it’s restricted, i.e. a hotel has to give you a special password or you have to pay for it via a website. That’s where the friction comes, and it gets even worse with these systems that proxy everything and kill the session when you leave the browser (say, to send a tweet from a twitter app). Many of us will still need wifi as bandwidth isn’t ready for high-end uses like HD video - and also while data roaming charges remain stiflingly high - but a built-in sim card is the only way forward as the default mode of connectivity. I’m currently paying £7.50 per month (~ $12) for 3GB/month download, and came with a new USB modem. At a rate like that, it’s a no-brainer for tablets.