Problems depend on the user's particular configuration. Generalizing from any installation experience - good or bad - is meaningless. And I don't think it's quite fair to write off problems as caused by malware or hardware failures.
I had 2 perfectly eventless upgrades to AU, but yesterday when I upgraded my wife's laptop I ran into what sounds like his point #3:
3) Cold boot and resuming from hibernation now takes AGES! Prior to the 'much awaited' update a cold boot took around 50 seconds and resuming from hibernation tool hardly 15-20 seconds. Now cold boot takes around 2-3 minutes and resuming from hibernation takes around 1.5-2 minutes. It always gets stuck on the login screen and processes the entered password as if it is negotiating from servers situated on Pluto!Except my delays were more like 5-10 minutes. That is, 5-10 minutes before I powered off the laptop and tried again. But after the 5th or 6th reboot everything was fine. And who knows - it probably would have fixed itself after the first boot if I'd have let it sit for 30 minutes. Windows must have been doing some initial configuration setup, or installing drivers, or just being perverse. But now it's fine.
I seriously doubt that malware gave up and uninstalled itself. And I doubt that a hardware problem cleared up (but that's certainly possible). In any case, there were no suspicious events logged (that I noticed).
I don't think either my 2 easy installs or my heart-stopping 3rd install are representative of anything but themselves.