Reduced risk of threat?

"Newly discovered security vulnerabilities to the operating system will not be patched." Let's look at this from anther perspective. Remember, as the OS ages, it loses users and as users fall away, the appeal of attacking the OS diminishes. Now, this will take a long time with XP because so many business functions depend on it.

"If you are using your computer as a standalone machine...there's not much risk at all." Can't viruses be passed via infected files on optical disks and flash memory? I had thought about using a stand alone system for a little bit but decided it wasn't worth it. You are right, though, most risks come through the internet and spread through networks. If your computer is on a network, it is at much greater risk of infection if one computer on your network gets infected. Think of it this way: if you child is in daycare with other kids, he is much more likely to get sick than if he's in a bubble all by himself.

"some folks simply can't get the new operating system because of financial issues.. " I would add a number of reasons for having a stand alone computer and XP is a good OS for it. For example, my dad was using an old (2001) copy of Quicken financial software on a Vista machine. Ironically, his 98 machine (upgraded from 95 years ago) was still ticking perfectly until he threw it in the trash. Having XP or even 98 or NT machines make a lot sense as stand-alone systems. You don't need the latest os for these machines.