Even on a down day like yesterday, Apple (Nasdaq: AAPL) continues to inch toward fresh all-time highs.

There's clearly no lack of love for what has become the country's most valuable company. Are we getting too euphoric?

CNBC had Eric Jackson -- hedge fund manager of Ironfire Capital -- on yesterday. As a Forbes contributor, Jackson wrote a column last week suggesting that Apple could be worth $1,650 by the end of 2015.

It's a big number, and the target date is far enough away to make people forget about it if he's wrong.

Spoiler alert: He won't be wrong.

Mac attack
A good chunk of Jackson's thesis is that Macs will grow in a major way. I'm not entirely sold on that, but let's take that out for a spin.

Apple sold 4.9 million Macs during the holiday quarter. It's a big number, but it basically amounts to just 5% of the nearly 92.2 million PCs that sales tracker Gartner estimates were sold during the period. Apple may have 11.6% of the domestic market -- growing at a time when its Windows-fueled rivals have largely stalled -- but it's still a bit player overseas.

Let's clear up what we mean by Mac sales. We're not talking about clunky desktops, though that's part of the Mac story. It's just that Apple is selling three times as many portable MacBooks as it is Mac desktops.

Jackson feels that Apple could sell 55 million Macs (desktops and portables) in 2015, more than tripling the 17 million it sold last year.

That's overly optimistic. The "good enough" computing revolution is real. It will be iPads and iPhones that drive Apple higher in the coming years. There's a good chance that students may warm up to Macs as iPads take over the classrooms with digital textbooks, but the real growth story here is the iOS platform that powers iPhones, iPads, and iPod touch devices.

Macs will continue to grow faster than the rest of the PC market, but expecting global sales to more than triple in three years is a stretch.

Take 500 million tablets and call me in the morning
Another part of Jackson's theory is that there will be 500 million tablets sold in 2015 -- and that Apple will sell 300 million of them.

Yes, Apple has better than 60% market share in tablets now, but I don't know how well it will fare in a future where Google's (Nasdaq: GOOG) Android will probably be the platform of choice for smartphones and tablets. That's OK. Apple will continue to be the one making the lion's share of the profits.

And, hey, 500 million is a huge number. That's more than the number of PCs sold worldwide last year. And the 300 million Apple figure means that 1 in every 20 people will buy an iPad that year. It's a metric that may prove true in the U.S. and select Apple-friendly markets, but a global average? I don't know about that. The wildcard here is if classrooms flock to the iPad without a viable Android-based alternative. Let's also not dismiss Microsoft (Nasdaq: MSFT) entirely here. It's been a nonfactor in tablets, but that may change as Mr. Softy's operating systems for both mobile and PCs grow more tablet-centric.

Bring out the bull suit
Disagreeing with Jackson on the market's demand for Macs and iPads doesn't sound like a good way to arrive at the same $1,650 figure, but let's be honest: Apple's biggest drivers three and a half years from now may not even exist yet.

The iPad wasn't around on this date two years ago. Go back exactly five years and we were still months away from the first iPhone. However, both of those product lines now make up more than half of Apple's revenue.

Does this mean that Apple is going to have to pull another rabbit out of its hat to grow into a $1.5 trillion valuation by the end of 2015? No. However, I think the inevitable iTV -- and perhaps more importantly the Web-served television service that will eventually follow -- will move the needle. An Apple TV won't be as replaceable as the iPad and iPhone. I don't see anyone swapping out their TVs every two years. However, Apple's ability to disrupt nearly any industry it enters has to tickle your sense of whimsy.

Right now, Wall Street sees Apple earning $77.09 a share in fiscal 2015. A price tag of $1,650 would give it a fair earnings multiple of 21 -- and likely a forward profit multiple in the high teens. When you consider that Apple's history with analysts consists of Wall Street perpetually jacking up their profit income targets, fiscal 2015's reality will likely be even better than that.

Yes, Apple has had a monster tear over the past few months. Jackson even conceded on CNBC yesterday that he wouldn't be surprised if Apple saw $500 before it saw $700.

On that point, I disagree. Apple will correct. It has in the past. It will in the future. However, given Apple's ever-improving fundamentals, the floor is as much a moving target as the ceiling.

Bet against Apple at your own peril. 

Apple jacks
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