We're not post-PC, we're plus-PC. But the problem with plus-PC is that it leaves the PC as 'boring but useful'.
Have some sympathy for the PC in the new world of devices. The PC is caught between a rock and a hard place. Other devices can pick and chose features and options to hit a price point or a battery life or a design style, but Windows has to keep the weight of its legacy heritage, its backwards compatibility - and with the x86 architecture that's literal weight, for the large hard drive and the battery and fan the processor needs.
That's not just because PC users need it. It's that other devices can only succeed despite giving you only a specific slice of functionality because the PC is the ultimate fallback device.
Need to update your phone? Even with an OTA update, you'll be plugging it into a PC to do a backup first. Your SD card is big, but all those photos are ending up on a hard drive as well as in the cloud - unless you're really brave. You might have a Kindle, a tablet, a smartphone and a Chromebook that cover 80% of what you need to do between them, but you're only comfortable with 80% because if you ever need to edit a PowerPoint animation, work with a pivot table in Excel, trim the last 15 minutes of dead air from a recording you left running too long, see several documents and Web pages side by side on a big screen or just print out your boarding pass or rental car reservation, you can fire up the PC and be sure you can get it done. (And yes, I expect for any single complex task I point at you can find an app that does pretty much that, but I've yet to see something that's not a PC or Mac that can handle every single one of them, guaranteed.)
PCs; as the Yellow Pages ads never wanted to admit, you need them around for the boring things in life, that the latest sexy apps can't handle on those thinner devices. But that can leave the PC itself looking pretty boring by comparison. You can use Twitter just as well, if not better, on a PC but when you can do it well enough on a super-slim tablet that doesn't warm your lap and weigh down your knees, why wouldn't you?
Intel has only recently got the point that power and battery life matters, and it's barely got it; it's talking the talk on touch but not walking the walk. The brave new Ultrabooks that are supposed to transform the PC back to sexy? The target is five hours of battery life with a stretch goal of eight hours and PC makers can put in whatever cheap digitiser they think will fit their tiny profit margin, while they compete with stylish Macs that use expensive components and deliver anywhere from three to six times the profit margin for Apple.
Microsoft is better; the Windows team has the touch religion to the point that they can sound like revival meeting evangelists and Windows 8 PCs that go into Connected Standby are supposed to stay up to date with email, tweets and messages and only use 5% of battery over the 16 hours between me getting home and putting them to sleep and waking them up when I go back to work in the morning (it's not that the Windows team doesn't want you using your Windows 8 tablet in the evening, it's just that if you don't use it or plug it in, it still has to be ready to go). But getting that viewpoint across was a hard-fought internal battle and it's only for the low-power systems that support Connected Standby, and only for Metro apps. I've met folks working on Windows who still think that the power that matters is how powerful desktop apps are for getting things done.
Actually, that aspect of power does matter a lot. Some of us still use two huge screens full of windows, all packed with dense information. We have an IDE open, or 25 browser tabs, six emails and ten OneNote notebooks on screen at once, or video editing windows with effects, soundtracks and titles running, or Excel spreadsheets modelling climate or the national debt or some other out of control system. What's moved onto devices is mainstream, casual computing; reading, browsing, simple editing, simple updating. The 80% stuff. PCs are workhorses and workstations and real work - whether you do that for fun or money.
Windows 8 is about making PCs for the 80% stuff as well, with tablets and glanceable, live and fresh, fast and fluid touch interfaces. At least on the surface - underneath it's the biggest architectural rewrite of the operating system and development environment in a long time. It's an attempt to straddle casual computing and workhorse computing in a continuum that goes from recording TV to browsing the Web to doing my taxes to building the Web (and to streaming out a TV station - Windows Server is the same Windows architecture). It's computing for the next generation of PCs with Kinect sensors for gesture navigation and voice control as well as for touch screens, rather than just a few new features to perk up today's PCs.
Or at least it should be.
We haven't seen the next generation PCs and the next-generation natural interface in anything more than research projects and what-if demos. We haven't even seen the final look of the Windows 8 interface beyond the tablet-friendly Start screen; the Windows team has said both the Metro interface and the desktop will evolve from the current look in the developer preview (although the Metro Start screen is never going to be optional when it's the only way to get apps using the new WinRT programming model). To make the PC feel sexy and exciting and powerful in a good way, rather than boring and powerful in an offputting way, to take advantage of the power that enables that backwards compatibility rather than letting all the 80% devices take advantage of the PC by turning it into nothing but a fallback device, Microsoft needs to be getting us excited about what the Windows 8 PC can deliver beyond just catching up with the sexiness and lightweight-ness of tablets and smartphones and the like, in terms of what we're actually going to get. To make the other gadgets work, I have to have a PC around in the background - but why will I want to have it around and have it on?