In the last few years our use of computers has undeniably changed, but particularly for those of us geeky enough to worry about what devices we use for what purpose our access to computing tools and perhaps more critically Internet services has radically changed.
We used to be the guys and gals that had an expensive computer that we used too much and knew enough about Windows to help confused relatives with their Antivirus software. Now we're the trendy ones who carry a more expensive and powerful computer in our pockets than many of our parents have ever owned at all. The particularly geeky of us, it seems, really don't compete without The Trinity: Computer, Tablet and Phone.
More socially representative members of society probably aren't quite as gadget-loaded as we are. My Mother for example has an Android smartphone and more recently an Android tablet. She never really felt the need for a computer of her own previously; her husband has one, and could facilitate her needs when they arose. Her smartphone is work-related. Her Nexus 7 however is a Christmas gift that she chose and to me this represents not a shift in the needs of society for computers but a shift in computers to better integrate into society's needs.
Who'd pick a desktop over a tablet to do some e-mail and read webpages or watch YouTube? Almost all of us will opt for the opportunity to do those things while reclined on the sofa using something handheld.
Really, the desktop and notebook computer, that traditionally have encompassed the whole personal computing paradigm, are being robbed of their slave audience by the convenience food of silicon technology; one that comes with its own set of potentially harmful additives (the subject of another discussion perhaps). At the same time it is a great enabler, people who might never have bothered with a personal computer are buying or being gifted little black slabs and finding touch interfaces and user-centric design far easier to wrestle with than the nested-complexity interfaces of years just past.
As nerds, we're subject to the same use cases and needs as anyone else you might think of. We love convenience just as much and we love tech even more. We all have tablets for the same kinds of reasons my Mum got hers, though we argue about them with each other far more. In many ways we don't even think of these as computers so much as a tool for a job much like we think of a novel as a story rather than a leaved block of wood pulp and sprayed-on ink.
This leaves the poor old PC in an odd spot. It's still essential for the proper running of most of our professional lives. Tablets have limitations, often such that most people need never encounter them during personal use but such that very complex, finessed or strenuous tasks need the additional raw power or flexibility of a more traditional platform. This is most evident perhaps in the corporate environment but also to all manner of hobby, gaming and entertainment uses. This might lead to some forgoing a tablet altogether, but for many of us the allure is too great; two awesome toys is better than one, right?
Besides, that multimedia library won't stream itself to the TV in the home office and the surround-sound system in your bedroom. Bow-chikka-chikka.
Then there's the smartphone, the zeitgeist itself. It has a lot to answer for: it's really the catalyst for the whole "Post PC" (to borrow an awful buzzword) movement. Tablet computers owe more for their existence to the smartphone than to the IBM clone or Apple Mac. Smartphones proved the validity of mobile device operating systems as full-fledged computing tools in the space of a year where previous attempts had been hobbled by poor design and technical limitations. The scale of the phone was also important as mass production of capacitative touch receptors was still prohibitively expensive and did not have the beneficial economy of scale that would enable ten-inch and upwards interfaces that we take for granted today.
Most important to the smartphone's success is probably the integration of high-quality standards-compliant web browsers and later internet-driven native applications. Access to the internet, it's resources and it's associated communications tools anywhere with a half-decent mobile signal is why a smartphone is smart - and the reason it provides a real convenience and benefit over the commonplace feature phone. The downside is it's tradeoff, portability vs. scale. While many of us nerds can debate the merits of screen size from now until the end of time, if it's a convenient size for your pocket then it's generally understood that something a little bigger is better when it's available.
So what's happened to our computers in the last few years is really a matter of convenient use, and the reason we've trippled the number of 'srs bsns' computers in everyday use has everything to do with the right tool at the right time opposed to being limited to the one thing that worked. It's probably true that most of the things we do on a computer are entirely achievable with a smartphone alone, but while smartphones are excellent and ever-ready there are times when it's simply not the appropriate tool and sometimes the appropriate tool is the one that offers the most situational convenience. We have three computers so that there is always an appropriate device at hand, one that offers the best user experience for our tastes and needs according to circumstance and environment. The most pocketable, the most sofa-able or bag-able, the most powerful and capable.