Apple (AAPL -2.19%) still hasn't announced when its new smartwatch will go on sale beyond "early 2015." However, now that the Apple Watch launch looks to be right around the corner, analysts and tech pundits are becoming increasingly vocal about their predictions for its consumer acceptance.

Several pundits' predictions about Apple Watch sales have been in the news recently. Photo: Apple

Indeed, since the beginning of the year, Apple Watch news has been dominated by bold predictions about the Watch from both bulls and bears. However, extremists on both sides of the argument are almost certainly off-base.

Biggest product ever?

On one side are the hyper-bulls. Trip Chowdhry of Global Equities Research was in the news earlier this month after predicting that Apple Watch will be Apple's "most successful product ever." He projects that Apple will sell 40-42 million in 2015 alone.

Chowdhry's spotty history of predictions should be enough to give investors pause. Back in March, he infamously declared that if Apple did not release a smartwatch within 60 days, the company would disappear, or at least become irrelevant.

The Apple Watch wasn't announced for almost 6 months after Chowdhry made that pronouncement, and 4 months later, it's still not on sale. Miraculously, Apple survived -- and Chowdhry went from raging bear to raging bull almost overnight.

A bigger reason to doubt Chowdhry's euphoria is that the Apple Watch is essentially an iPhone peripheral. It needs to be tethered to an iPhone to work. In fact, it requires an iPhone 5 or above -- whereas nearly a quarter of all iPhone usage still comes from older devices (mainly the iPhone 4S and iPhone 4).

The Apple Watch needs to be tethered to an iPhone 5 or above. Photo: Apple

With Apple Watch's market being restricted to iPhone users, there is a firm upper limit on how many Apple can sell. Thus, there is no way that the Apple Watch will be more successful than the iPhone.

If Apple Watch sales reach the same ballpark as the iPad in the next few years (around $30 billion in annual revenue, vs. more than $100 billion for the iPhone), Tim Cook and company will be delighted.

But beware the doubters, too!

On the other side of the coin are the Apple Watch skeptics. Prominent venture capitalist Fred Wilson's bearish outlook for the Apple Watch has attracted plenty of attention in the news recently.

As part of a list of predictions for 2015, he wrote, "The Apple Watch will not be the homerun product that iPod, iPhone, and iPad have been. Not everyone will want to wear a computer on their wrist." As noted above, he's right with respect to the iPhone. $100 billion plus products don't come around very often.

However, surpassing the iPod should be quite easy, and even matching the iPad is a plausible goal. Apple sold about 19.5 million iPads in that product's first year on the market. But when the iPad was introduced, the iOS ecosystem was tiny -- Apple had only sold 51 million iPhones total between 2007 and March 2010. By contrast, Apple sold far more than 51 million iPhones last quarter alone!

There are hundreds of millions of iPhone users across the globe. If Apple can convince just 5% of the iPhone user base to buy an Apple Watch in the next year, it will instantly have created a new $5 billion-$10 billion business (depending on the average selling price). If 10% of iPhone users buy an Apple Watch, that could push sales as high as $20 billion.

Apple Watch may quickly become a $10 billion business. Photo: Apple

This would make it far more successful than the iPod, for which sales peaked at less than $10 billion in 2008. Moreover, as Apple Watch adoption moves beyond early adopters in the next few years, sales could potentially rival those of the iPad.

So while "not everyone will want to wear a computer on their wrist," the Apple Watch may still be a "homerun product" on par with the iPad -- or at least the iPod. Plenty of people will pay up simply to avoid having to pull out their iPhone every time a notification comes in. Health and fitness apps and the slew of third-party apps that will no doubt appear soon after launch will be an added bonus.

The truth is somewhere in between

Perhaps it's not surprising that the recent Apple Watch news is dominated by extremely bullish and extremely bearish predictions. Big, bold predictions make better headlines than the truth, which is that the Apple Watch will not be nearly as big (in terms of revenue) as the iPhone, but should easily surpass the iPod and may even rival the iPad.

If Apple bulls cling to the notion that the company will someday introduce "the next iPhone" -- a product that can bring in more than $100 billion in annual sales at roughly 50% gross margins -- they will be doomed to perennial disappointment. The Apple Watch can become an important sales and earnings growth driver for Apple without meeting such heroic targets.