Terms That Need to Die #2
Current Trend: Having a PC as opposed to a Mac.
personal computer: a small digital computer based on a microprocessor and designed to be used by one person at a time - Princeton WordNet
No, I'm not saying you should get a Mac instead of a PC. I'm saying a Mac is PC and a Windows-based machine is a PC. They're both PCs and marketing divisions need to stop destroying jargon for their own selfish desires.
Windows != PC
There was an age where we could distinctly divide Apple machines from the rest of the world. That time ended with the death of the PowerPC architecture. Everyone is running on x86, OSX and Vista are interchangable.
On the side, I really don't like how this completely obscures Linux from the whole PC collective. Commercially backed Linux distros like Ubuntu and Red Hat are not to mindlessly ignored or grouped with Windows.

"Hi, we're actually both PCs..."