April 2010 doesn't seem so long ago, really. A child born then would be 2 and a half, probably walking, maybe talking if not simply in gibberish. And April 2010 was the when Steve Jobs and co. debuted the iPad. After the announcement, there was some question whether a tablet would matter, whether there would be any consumer uptake. See for yourself by searching "Steve Jobs introduces the iPad," then read the user comments after news articles, like this one. I'd love to know how many of those nay-saying commenters are submitting their comments via a tablet today.

In the 32 months that have followed, Apple has released 4 successors to the 1st generation iPad. Four. There was the 2nd gen iPad, which was lighter yet faster. The oddly-if-not-poorly named 3rd gen rocked a retina display, though buyers paid for it in extra weight and thickness (and heat). Then, just 2 months ago in preparation for the 2012 holiday season, Apple disrupted the annual (ish) refresh cycle way in advance, outing not 1 but 2 models–the 4th gen iPad and the iPad mini.

The fact that Apple released 2 new models within a 6 months of the previous release had some fans up in arms. Those wanting to maintain the 'latest-and-greatest' hardware status were miffed, then scrambling to figure out a way to offload the hot-and-heavy 3rd gen iPad to offset the cost to upgrade.

While Apple makes great strides to make their customers happy, Cook and team have had to keep one eye on the competition as well. They didn't want to lose opportunity heading into the holiday season with a stale tablet lineup. Did they make the right call? We'll find out from Cook himself during the January 25 quarterly sales report out call.

You may be thinking, would a tablet introduced in April really have been considered stale by December? In 2010, the answer would have been "no way." The 1st gen iPad was the only horse (that mattered) on the track. In 2011, the answer was "well...no." Apple still had the upper hand, though 2011 brought a pool of (primarily Android) tablets to market. Amazon introduced the Android Fire in November. But the iPad was still the golden child, and customers generally used the word "iPad" when referring to tablets in general.

2012 has been dramatically different in the tablet realm. In the circles I travel in, people are much less inclined to say "if I get a tablet" and instead suggest "when I get a tablet." Of course, this is for the dwindling percentage of those who do not already have a tablet. Tablets are popping up everywhere, in the classroom, in the conference room, in the living room. The window of time from introduction to acceptance was considerably shorter for tablets than their little cousins, the smartphones.

I just read an article on fool.com which states the IDC forecast for total tablet sales by 2016 has recently been adjusted. Earlier this year the prediction was for 198 million total sales in 2016. The updated projection–282 million.

It is clear we have crossed a threshold. There is no more "if." We are into "when."

Folks, we are in the post-PC era.