XP eat your heart out, no upgrade from XP to 7,
Do we know this for sure?
In any case, sometimes it's good to reinstall anyways. Especially since you'll likely want to upgrade to the 64 bit version, which I'd highly recommend for future memory expansion and increased security measures such as PatchGuard.
and others, it would seem, are afraid they don't have the mental capacity to learn a new OS.
With Seniors, this could certainly be a real issue.
The other half of the problem... so-called experts who are stuck in a rut and think the tried and true is best
Yup. "I've been using this for years with no problems, and I don't possibly see how this new thing is better" is common. Problem is, many of them don't even try the new stuff, leading to a purely one-sided argument.
What did I miss out on?
Not much. You just took more chances sticking to an OS with inferior security. In addition, Windows 7 will have the same improvements that Vista had: Improved search, improved troubleshooting, a hardware accelerated UI, and the ability to pre-load software into memory, just to name a few.
Basically you decided to delay getting all of the benefits of Vista.
The biggest benefit is security. Not just UAC, either: For a lot of people, switching to Vista also means switching to a 64 bit OS, and this gives them PatchGuard, which helps keep malicious code out of the critical kernel sections and makes it nearly impossible to rootkit.
In addition, Microsoft has released many patches that are "Critical" in XP because XP runs pretty much everything with Admin privileges, but only "Important" in Vista because Vista's security measures protect system files and default to being run at lower privilege levels.