Story highlights With tablets, there is now no "one-size-fits-all" answer

iPads remain on top, but smaller, sometimes simpler competitors, have made in-roads

Rumors say Apple may counter with iPad 'mini," while Kindle Fire might get bigger

When it comes to tablet computers, size matters -- a lot. But these devices are definitely not one-size-fits-all. And like Alice in Wonderland, the "right size" for tablets keeps shifting.

That's making the tablet market curiouser and curiouser.

Many iPad users treasure the Apple gadget's approximately 10x7-inch expanse, and I've seen some bristle at the suggestion that this size might be unwieldy. Meanwhile, users of the Kindle Fire or Nook Color often prize having a tablet that slips easily into a pocket or purse for half the price (or less) of an iPad.

There is a large and fast-growing consumer demand for tablets across a wide range of sizes and price points.

In February, analysts at iSuppli estimated that 3.9 million Kindle Fire units were sold in the last quarter of 2011. That's only about a quarter of the number of iPads estimated as being sold during that same quarter, but it's still pretty respectable for a new device.

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The diversifying tablet market also includes the oddball Samsung Galaxy Note -- a moderately pricey, stylus-bearing smartphone/tablet hybrid. Initially greeted with skepticism, this device ended up selling five million units in its first six months. And soon it might come with Ice Cream Sandwich pre-installed

Could the iPad shrink? Rumors have long been swirling that Apple might be preparing to launch an "iPad mini" model that's closer in size to the Kindle Fire.

CNET Asia reported this last week: "According to Japanese Apple news site Macotakara, Apple's working with LCD suppliers to get a 5-inch panel with a pixel density high enough to be able to call it a Retina Display. That's according to 'a reliable Chinese source,' the site said. ... That smaller device would arrive sometime next year, Macotakara suggested."

Of course, before we learn the truth of the elusive mythical iPad mini, the next version of the Kindle Fire, which could be released as soon as May or June, might feature a model with a larger screen as well as upgraded specifications. This week, Fire2.net claimed that "newest reports from Taiwan suggest... that there probably won't be a 10-inch Kindle Fire 2, but two different 8.9-inch tablets and a smaller 7-inch model."

Yes, I know, these are all just rumors, based on information allegedly leaked from Apple's and Amazon's supply chains. But when it comes to upcoming tablet models from highly secretive and competitive electronics giants, that's all we've got to go on.

One thing is clear: the Kindle Fire and Samsung Galaxy Note are runaway market success stories, despite their smaller screens. Perhaps even because they're smaller. Many consumers clearly want and will use smaller tablets -- both cheaper, simpler models and costlier, more fully featured ones.

Certainly, Apple has noticed this development even if, as usual, they won't talk about it.

So for this reason, I wouldn't be surprised to see Apple eventually launch an iPad mini. Maybe not this year, but perhaps some time in 2013. However, it might not necessarily cost much less. Apple might decide to take the "small is beautiful" approach and market an iPad mini as providing extra, or at least different, value -- not as a compromise.

That might be totally appropriate, since the perfect size is a matter of preference. As Alice told the Caterpillar:

"I should like to be a little larger, sir, if you wouldn't mind," said Alice. "Three inches is such a wretched height to be."

"It is a very good height indeed!" said the Caterpillar angrily, rearing itself upright as it spoke (it was exactly three inches high)."

The opinions expressed in this post are solely those of Amy Gahran.