Re: What's your definition of "dying"?
> 3) Microsoft improved Windows security and reduced (but didn't eliminate) malware, which used to be one of the primary reasons a PC got "slow" and was replaced
Now the reason a PC is slow is the AV software.
I suspect most PCs are used in business which isn't so enamoured with tablets, so the sales decline isn't permanent, but the life-cycle for clients is longer. The XP->W7 jump boosted resource requirements but it appears that not even MS can bloat an OS that fast. I suspect there will be a "boost" (for vendors, a "downer" for customers) when all those XP VDI solutions have to move to W7.
Some apps are moving to servers. You don't run the entire company accounts on your PC, it runs on a server. Gmail doesn't use much in the way of local resources. Some companies are ditching dedicated websites for facebook so again, more consolidation.
There's been little innovation in the consumer end of the IT infrastructure industry. Where are the PCIe NAS blades providing the local host with virtualised NAS storage and a NIC out to the network for when the host PC is "off." How many graphics cards can power down their fans when they aren't doing much? What happened to 100m optical Thunderbolt? Why are dual-gig ports disappearing from desktop boards when they would enable iscsi to be used effectively and why is it *still* so difficult to get adsl routers with all gig switches? Why is it so hard to get a monitor with a webcam built in? Why aren't graphics cards "hot pluggable" so I can turn off my 3d gaming monster and use the built-in graphics on my desktop board without pulling the 3d card out of the box? Where are the BSD ARM router/firewalls? Where are the range-extender access points for consumer wifi, so I can get a decent signal on the other side of the fridge? Has no-one thought that gig-ethernet on a tablet/phone might be useful when running HD mpeg2 traffic, or at least a cradle with PoE for ultra-fast networking, sync and charging. Don't even get me started on 1366x768 laptop screens or "ultrabooks" that have no VGA, DVI or DP outputs. CPU has never been so cheap, but we're intent on moving it as far away from the users as we can so UI latency becomes almost insurmountable. Lotus 1-2-3 ran in a few hundred Kb on 16 bit hardware and we can't get a browser-based spreadsheet to run on a quad-core 64bit cpu with gigs of ram at a decent rate.
It isn't just the hardware industry, It is probably changeable, but the standard Outlook UI is an abomination, Valve still doesn't have download scheduling, Android - a device that's designed to be on high-loss wireless networks seems to have no proxy abilities and Apple, which made its name in high-quality display/UI, steadfastly refuses to work with blu-ray.
/grump