Microsoft has a special deal to upgrade to Windows 8 Pro for $39.99 until the end of January. This should be a really attractive deal as Windows Pro upgrades are usually around $160.
Interesting deal, but it kind of proves my point that most people don't know about it, unless they are proactively searching for a Windows 8 upgrade. In general, I don't think PC users are used to upgrading their OS without kicking and screaming all the way there - mostly due to painful upgrading processes of the past. Again, that's one thing were other operating systems are way ahead of Microsoft. For example, they could have installed a mechanism in Windows 7 to broadcast a taskbar reminder about upgrading to Windows 8, offering the $39.99 upgrade price, and talking about how it's quicker and easier than ever. That might have helped.
Now that I know, I'll probably upgrade my desktop this weekend. So that's another 0.0000000001% for Microsoft.