Can you feel it? No, not the chilly temperatures across the Northeast on this last Sunday in March, which signal that despite what the calendar says–spring may not yet have fully sprung in this part of the world.

I’m talking about the last weekend before the arrival of the next big, big thing.

Because after next Saturday, it is quite possible that the old cliche might be true and things might not ever be the same again. Next Saturday is when Apple is set to deliver the first wave of the much anticipated iPad. And while it would be easy to write off this event as just the arrival of the latest gadget in the electronic universe–given the track record of Steve Jobs & Company, that would seem to be short-sighted and ignorant of history.

It was 25 years ago that I bought my first Macintosh computer with my own money (a MacPlus, for the detail obsessed). It nearly caused my bride of one year’s time to divorce me, because it was money we didn’t really have. But I really had to have this wondrous new computer that was redefining the idea of the “personal” computer. (And we had enough of a credit rating to allow me to finance it.)

That really is Apple’s legacy as a company. Redefining a genre in personal technology. The Mac did it for the personal computer, introducing the mouse and the graphical user interface as a standard. The PowerBook redefined the laptop computer category. The iMac redefined the way home computers looked and how they interacted with the internet. The iBook redefined how laptops connected to the internet with the first practical deployment of WiFi for wireless connectivity. The iPod redefined the way we carry, play and even buy our music.

And of course, the most recent redefinition to come from that company in Cupertino, California–the iPhone. Which, for better or worse, has redefined not only what we expect from cell phones, but arguably how we interact with the internet as something that can accompany us wherever we go.

Which brings us to the dawn of the era of the iPad.

There has been a lot of speculation and often derision, that the iPad is just an iPhone with a big screen. And while there is some truth to that, given that the iPad will share the iPhone’s software architecture, it would be foolish to write the iPad off as that simple a concept.

Where the iPhone introduced the concept of combining a cell phone, an internet browser and a media player into one pocketable device–I’d argue that it was Apple’s introduction of applications or “apps” to the iPhone (and our vocabulary) that redefined the next generation of computer software–dedicated and downloadable programs that could allow the basic iPhone to become a device capable of an even wider array of functions from GPS navigator to portable game player.

Pretty much whatever the owner wanted it to be, aside from being a pretty cool combination of phone, internet and iPod.

This concept was so strong that even removing the phone functionality (to create the iPod Touch) just kept growing the user base. Which still keeps growing.

And thus, we arrive at the moment of the iPad.

In classic Apple fashion, the product introduction has only been enhanced by the months of waiting in between the device’s coming out party back in January and its going on sale to customers in the first days of April. That time has allowed some skeptics to become supporters, even no less a character than “Fake Steve Jobs” himself (Newsweek writer Daniel Lyons).

Let’s be clear, the iPad won’t cure cancer or bring about world peace–and why should it? The detractors of Apple’s efforts have always resorted to setting the bar so high that it is unlikely anything, or for that matter anyone, could possibly clear it.

But what the iPad likely will do is redefine our thinking–yet again. About how we consume information and media. About how we read books, magazines and newspapers. About how much more pervasive the internet will become in our daily lives.

Barron’s has released its annual list of the best CEOs in the world. They have dubbed Steve Jobs as the “world’s most valuable CEO.” This is the same CEO who once told the man he asked to lead Apple at the time (John Sculley, then CEO of PepsiCo) “Do you want to sell sugar water for the rest of your life or do you want to come with me and change the world.” Sculley, who would subsequently drum Jobs out of the company he co-founded–only to fail miserably and open the way for Jobs himself to return and take it to an even higher level of success.

It would be foolish to bet against Jobs, Apple, and their latest creation. But I’d take it to the bank that a number of things will never be quite the same after the iPad lands in people’s hands on April 3rd.

And probably more things for quite some time after that.

Postscript: Journalist and expectant father Mark Joyella puts this all a little more succinctly and powerfully in his kind re-tweeting of this blog: @standupkid “Last weekend before everything changes: My soon-to-be-born child will never know a world without the iPad”

Indeed.