Apple Inc. (Nasdaq: AAPL) released a new tablet computer, a 10-inch touchscreen device called the iPad that can deliver video, music and other online content. The arrival of the tablet has been, as is Apple’s wont, shrouded in secrecy.

All that remains secret is whether the iPad will be the company’s next profit catalyst or not, and how well it will actually sell when it becomes available in about 60 days.

But cutting through the hype and the niftiness of the device — which Jobs limned in breathless superlatives — investors need to ask themselves three key questions: Will people buy the device, will it have a significant effect on Apple’s revenue and does it create other investment opportunities within the industries it will disrupt?

Let’s take these one at a time.

Will people buy it?

The conventional wisdom suggested a price between $600 and $900, but Jobs said the devices will start at about $500. With the price lower than expected, the iPad seems like a better deal, even with $30 a month for an unlimited data plan.

With price presenting less of an obstacle than some had forecast, the question is whether Apple can deliver sufficient functionality. That’s a reasonable bet, but not a sure thing: Apple and others have tried the tablet market before and been unable to build devices consumers liked using. But given the leaps smartphones have made — the iPad has one button and a touchscreen keyboard, a familiar interface for Apple devotees — it seems reasonable to conclude that a supersize iPhone, with access to apps, navigation and content, will deliver a user experience like the iPhones, which is to say a good one. Jobs, demonstrating the iPad, says the device allows for more “intimate” Web browsing.

Having said that, though, most people willing to chunk down a few hundred dollars for a smartphone already have one. People who love, love, love Apple products — well, they already own a pricey Macintosh. Folks who have embraced ebooks have bought a Kindle from Amazon.com Inc. (Nasdaq: AMZN). Portability junkies can buy a pretty well-equipped netbook for less than $500. Everyone has a flat-screen TV. So one has to question whether Apple will be able to pack enough niftiness in this new product to make consumers say, “I have to have that, too.” (The comparisons to the Kindle DX, which is a little more expensive, look past the fact that the iPad is backlit, making it tiresome to read for long periods, unlike the Kindle, which uses eInk technology that is more akin to paper and less hard on the reader’s eyes.)

 People legitimately need cell phones. Most people probably consider a television a necessity, along with a computer. But a portable device on which to watch movies and read the newspaper and listen to music — and which costs as much as $829 — is a wholly nonessential luxury purchase. It is a digital Harley-Davidson.

Some “early adapters” will buy the tablet. Because of the uptrend in handhelds since BlackBerry built one people found useful, consumers are more amenable to the iPad idea than they were in the era of the Apple Newton (a handheld from the early 1990s) or Bill Gates’ tablet PC, circa 2001. Even so, it’s unlikely the iPad will achieve the mass following of the iPod or the iPhone.

Will it have a significant effect on Apple’s revenue?

A million units at an average $650 each — the iPad costs from $499 to $829 depending on features — is $650 million. That estimate would put the tablet at roughly half Apple’s music sales, which amounted to $1.2 billion last quarter. Apple booked $5.5 billion in iPhone sales — 35.1% of revenue — and sold $4.5 billion worth of computers. The iPod brought in another $3.4 billion. So for this new product to have a meaningful effect on sales and earnings that would translate into a significant increase in Apple’s share price, the tablet would need to be an absolute home run. The odds that the tablet will come anywhere near iPhone sales, which totaled 8.7 million last quarter, seem remote.

That being said, the iPhone costs roughly $175 to make and brings in roughly $632 each, with cell phone carriers subsidizing the cost to customers. (Speaking of the iPhone, did you know StreetAuthority has its own app? Download it for FREE today and get our actionable investing ideas and market commentary the moment we go to press.)  Apple has always made great hardware and it’s never given it away. Jobs says Apple is offering six models at a range of price points because it wants to put the device into a lot of hands. We’ll see. There’s potential.

One factor that limits the upside is Apple’s share price, which is a little more than $200 a share. With such a high entry point, the price “seems” expensive to investors, even though Apple’s valuation, given the growth it delivers, is really quite modest.

The other thing to remember is that Apple shares typically don’t react in the short term to new devices. In fact, that’s really only happened once, with the iPhone, when shares jumped +8.3% on the day of the product’s unveiling. Other product releases — the several versions of the iPod, the MacBook Air and MacBook Pro — coincided with share price declines on the days the devices were announced.

Does it create other investment opportunities within the industries it will disrupt?

“Disruptive” technology isn’t a bad thing, it’s a game-changer that reworks an industry’s business model. The iPod is about the best example. Digital music players had been around for years when the iPod came around, but the device’s sleek design and intuitive functionality made digital music easy enough for the masses to embrace. And embrace they did. iTunes is one of the largest music sellers in the world. The iPod still has 70% of the digital music player market. As such, it turned the music industry upside down. (It also made small fortunes for Apple investors. After the iPod hit store shelves, Apple shares shot from about $9 to over $200 — a catalyst-fueled gain of more than +2,000%.)

In some cases, such disruptive technologies could create business opportunities. In the case of the tablet, of course, the question is whether the device will bolster book publishers and save the newspaper industry, as some have suggested it could.

This strikes me as throwing very long. Take a look at newspaper publishers. Their books show billions of dollars in dividends paid out during the past decade but not a dime of R&D. When tough times hit, they cut back expenses and coverage, and gutted staff. To think that they somehow will proactively exploit their new technology to reinvent themselves ignores not only the past quarter-century of history, but it also overlooks the fact that newspapers don’t have the cash — or the staff — to mount a challenge. No existing media company will be saved by the tablet. It’s far more likely that new, nimble content companies will emerge to profit from the opportunity, and the successful ones will be acquired by the few surviving media companies that have an eye toward the future and some cash left, like News Corp. (NYSE: NWS). Anything else is probably wishful thinking.

Investors who are interested in a high-tech company that’s always on the cusp of the Next Big Thing and can post impressive earnings results can do no better than Apple. Last quarter, Jobs & Co. posted a revenue gain of +32% and earnings growth of +50%. Apple consistently exceeds expectations, and I don’t think there’s any danger of that trend stopping. It’s a great company.

It’s a mistake to buy AAPL for quick gains from the tablet. A far better approach is to buy AAPL for its genius corps’ proven ability to innovate and its managers’ ability to deliver standout financial results.