I have an AMD processor that is roughly equivalent to a P4 that can run Windows 7 easily on a gig of RAM.

I think the key there is "a gig of RAM". I might be wrong (I've never actually installed anything above XP on any of my machines), but as I understand it insufficient RAM is the biggest culprit for performance problems in Vista and above. Mine has 512 MB, which XP is perfectly content with.

I have yet to see a system that could effectively run XP that couldn't also run Windows 7.

Really? Because I'm fairly certain the P4 w/ 512MB of RAM and an integrated Intel video card that I have at home won't run Windows 7 anywhere near "effective". XP Pro runs without any noticeable slowdowns, even when watching Flash video (YouTube, Hulu, etc.).

More topically, I would wager that the average person has no idea the difference between 2.5G, 3G, EDGE, or regular voice access. Non-technical people are just going to see two maps and notice that the red one has a lot more red than the blue one has blue. I'm not sure the fine print at the bottom of those ads stating that voice coverage is different is even large enough to be readable unless you have an HDTV.

If I remember correctly, Windows NT 4 (maybe Windows 95/98 too) was version 4 and Windows XP was version 5. More versioning info is here on Wikipedia.

... People who might be working on a Mac or some kind of *nix box. ...

MS Office is available for Mac as well, and has been for nearly a decade. It's even available at the Apple Store when you buy a Mac. The *nix install base is really the compatibility problem, although (as mentioned several times above) OpenOffice has rendered that nearly non-existent.

It's not just previous generations that prefer tube amps to transistors. The differences are not obvious until you try to overdrive them, at which point they break up very differently. Tube amps distort with a lot of coloring overtones that you just don't get from a transistor amp, which tends to sound crunchy and just plain distorted. The advantage of transistors is reliability as tubes will eventually blow out and need replacing. When I play my guitar, I almost always use tube amps for recording and personal playing for pleasure due to the better sound, but I usually use a solid-state amp for gigging due to the reliability.

The difference is that the various versions of Ubuntu (Kubuntu, Xubuntu, Edubuntu, etc.) are actually different and not the same thing with different features disabled. People who like Gnome will run Ubuntu, those who like KDE will run Kubuntu, older hardware will run Xubuntu for lower memory usage (or people who just like XFCE), Edubuntu comes bundled with education-specific software that is only useful (for the most part) to educators and students, and on down the line. Other than having useful features disabled in the cheaper versions, I can't see any appreciable difference between the different versions of Windows the way there is in the different versions of Ubuntu.

It's also worth noting that though the installer seems to work well, there is no "Uninstall" option, either in the KDE folder in the Start Menu or a KDE item that can be removed from Add/Remove Programs. I installed it on my XP box here at work to play around with it and I saw what I wanted to see to satisfy my curiousity, and I'm not sure how to go about getting rid of it (save just deleting C:\Program Files\KDE, which may or may not actually delete everything). I understand that this is pre-release, beta software, but there still ought to be a way to uninstall it.

I think you hit on exactly why kids aren't programming so much any more, that being the fact that computers don't ship with a basic programming language whose results can be easily seen anymore. When I was a kid, I had an old IBM PC-AT, which came with QBasic. Sure, it was QBasic, but I think that having that was better than having nothing at all because it at least taught me that I could make the computer do what I wanted it to do, not what someone else told me I could pay them money to have it do. I find the built in C compilers in Linux and OS X (if you install developer tools) fill this nicely, so long as you know they're there (I'm assuming you do if you know enough to be running Linux). There's really nothing like that thrill of writing your first program, seeing it work, and knowing that you made the computer do that.