This is my weekly column for Loose Wire Service, a service providing print publications with technology writing designed for the general reader. Email me if you’re interested in learning more.

I can hardly make my way to the drinks table at parties these days without someone accosting me, pinning me to the sideboard and impaling me on the question du jour: What is with all this Facebook stuff?

“It’s a good question,” I usually respond, determined to get something liquid inside me before answering. The truth is that the Internet is changing so fast, and changing us so fast, it’s hard to keep up.

Loyal readers of this column (hi, Colin!) will be familiar with my twitterings on social networking tools like Twitter, Jaiku etc, while the rest of you will remain bemused at best, at worst, tossing the paper aside, comfortable in the knowledge that none of this applies to you.

Well, I’ve got one word for you and it’s this: Skype. To understand why Facebook is so hot at the moment, and why those of you who think you can skip reading this column shouldn’t, we need to look at Skype, the free or cheap Internet telephone service.

From that we’ll see that technology, the Internet, all that stuff affects us all, and surprises us with its ability to change our habits without us really noticing. Or complaining.

Skype, you see, was nothing in 2004. Into 2005 it remained a sideshow. But then people realized it worked. Voices at the other end didn’t sound like frogs in a well. Suddenly everyone was using it to make calls, especially those people in parts of the world where phone calls were ridiculously expensive.

Then the Network Effect kicked in: The more people on it, the more people who weren’t on it felt they were missing out — if not financially — and they signed up.

And signing up didn’t just mean saying yes; It meant buying a headset, downloading software, installing it, signing up for Skype, and, if they wanted to make calls to ordinary telephones, buying credits, which meant using a credit card online.

For a lot of my friends, all of these were firsts. It was a delightful shock to behold. And once they had done those things, they were then ready to do the same thing with other services.

This was a big leap, one that is consistently underestimated by nerdy types who do them casually. Sadly, it was also underestimated by Skype and its new owners eBay, both of whom have failed to leverage the Skype revolution into anything more substantial.

When earlier this month Skype was down for a few days, there was only muted complaints from ordinary users — not because they don’t use Skype, but because they haven’t yet come to rely on Skype. (For what it’s worth, they should, and eBay should ensure that they do, by a) making it super-reliable and b) adding cool features that real people really want.)

Don’t be left out

Anyway, back to Facebook. Facebook was until recently — September 2006 — a social networking/homepage type tool for college folk in the U.S. Now half of its users — in other words, more than 17 million people — are outside college. (These figures are from Shel Israel, a consultant and writer who asked Facebook for stats.)

What’s interesting, though, is how most of these users aren’t techie types. While I’ve been trying to get friends of mine (those friends who aren’t techie, which means most of my friends) to sign up for these kinds of services for purely selfish reasons (there are only so many Twitter messages like “Restoring my computer to WinXP SP1 just for fun today! Wildness!” you can take) it’s only with Facebook that that actually happened.

And it didn’t happen because of me. Most of them signed up anyway, and were already there when I arrived. All sorts of people — friends from different walks of life, different continents, colleagues, ex-colleagues, readers (OK, reader), age groups, denominations and interests, genders, etc., etc.

Even journalists, not usually known for their hunger for the technologically new, are signing up. Facebook has tipped, in the timeworn phrase, in the same way Skype did. But why?

Well, the obvious answer is because everyone else signed up, so no one wanted to be left out. But I think that happened later. What happened first was that Facebook’s developers made it pretty easy to get started — add a photo, list the schools you went to, find a few friends who are also Facebook users.

Then there are compelling reasons to stay or come back — joining an interest-based group (there are 47,000 of them), loading a third-party application to do silly extra social things (more than 2,000 of them, including maps showing where you’ve been, your favorite movies, that kind of thing.)

The biggest reason, however, is that you find all sorts of people you hadn’t seen for a while, lost touch with, worked with or knew only indirectly; once you’re Facebook friends, the ice is broken and you’re sharing again, comfortable in a network of mutual friends.

All of this would sound quite so-so were it not for the fact that Facebook is geared towards social interaction. Not necessarily of the direct kind, upon which business networking sites like LinkedIn are built (“Please introduce me to Joe Bloggs in your network as I want to sell him my idea of Flying Underpants”) but the indirect kind: “Anyone seen Ratatouille yet?”, “I can’t believe there’s no English soccer on TV”, “My wife just left me for a lumberjack.”

Such utterances — posted on your Facebook page, but easily visible to friends in your network — invite comment and response, but don’t intrude in the way a direct message would.

I call it “displaced chat” — partly because I have pretensions to academia, and partly because I believe it describes a way for people to interact with others without directly approaching them.

Of course, we shouldn’t get too excited about this. Something will come along to dethrone Facebook soon enough (I give it six months; once everyone has basically hooked up with everyone they know or want to know, there’s not many places to go.)

But, as with Skype, it doesn’t matter. The gates have opened. A whole new bunch of people have embraced a technological innovation — social networking online – and found that it’s easier than they thought. And more rewarding.

I have no idea what the next big thing will be. But the biggest thing now is not Facebook: It’s that ordinary people are using it.