There's a battle brewing between your couch and your coffee table, and whoever wins will be one step closer to digital dominance.

Apple (Nasdaq: AAPL) seems finally ready to invade your living room. Bloggers, analysts, and pundits predict the company will launch its iTV platform before the end of the year, and they sound pretty confident this time.

If successful, the product could give Apple a slice of the $46 billion TV market -- and that's just in the United States. It's also a powerful strategic foothold that occupies 2.8 hours of our time each day and could help Apple further solidify its ecosystem.

If our digital lives are a battlefield, TVs are the high ground, but it's not exactly unguarded territory.

Assault on Fortress Xbox
Along with old-guard producers like Sony (NYSE: SNE), there's Microsoft's (Nasdaq: MSFT) Xbox 360, which offers many of the iTV's predicted features and has had six years to fortify its position. Consumers have bought 67 million of them, and now, more than 40 million people use its companion service, Xbox Live, an average of 84 hours a month.

If raw hype says anything, most think dethroning Mr. Softy will be simpler than conquering Paris right before lunchtime. But I think it'll be closer to Apple's Vietnam -- if not Waterloo.

Let's go through the Apple fan's usual lines of defense -- ecosystem, features, history, and brand -- and see if we can find a few weak points.

Turning the tide: why momentum doesn't matter
The go-to phrase for much of the Apple-rati is quite simply "They've done it before."

No, I don't have evidence proving the iPad and iPhone were actually flops. But I don't see how this history guarantees success now. Past performance doesn't predict future returns, as the saying goes. And even if it did, Apple would still be in trouble.

Apple shareholders have selective memories, particularly with Cupertino's last bust -- Apple TV. The company sold 1.4 million of the set-top boxes during the holidays last year and another 2.7 million of the boxes between January and May of this year. Sounds great, right?

Nope.

Consumers grabbed nearly 1 million Xboxes during just one week of the same period. Add in the Kinect, which passed the original iPad last spring as the fastest-selling gadget in human history, and you begin to wonder which company really has the momentum in this market.

Apple's failed in TV once, and to borrow the blogosphere's logic, this would suggest they'll fail again.

A break in the lines: where the ecosystem falls apart
Another buzzword you'll see a lot is "ecosystem." This is the idea that Apple can turn its enormous base of iOS users into iTV customers. Apparently, consumer electronics are like pewter figurines -- people need a complete set to feel whole.

To be clear, I'm not disputing the power of integration, standardization, and all the other "ations." The "halo effect" sent many iPod owners to their local Genius Bar in search of a Mac.

However, I don't see how this applies to TVs. Happy iPod owners switched to Mac because PCs were buggy, virus-ridden boxes of crud. There's not much for Apple to revolutionize in the TV, simply because there's not a lot wrong with it now.

The bottom line: Apple must add real value to a device that's been largely perfected. And because I don't know anybody who wants to read emails in surround sound, this value will have to come from invention -- not integration.

Misfire: Apple's secret weapons might be duds
"But the iTV will have features that Microsoft hasn't even imagined!" a devoted Apple-ite might say.

Like what? Siri and Facetime? That's what most have predicted, and it shouldn't impress you.

If Siri suddenly stopped sucking wind, somebody really should have told me. The Xbox and Kinect have voice recognition that's more than adequate for navigating content but far less annoying.

And while Facetime is truly useful, Microsoft has its own version that you might have heard of Skype is offered on more devices and has a much larger network of potential users.

But none of this matters because the Apple-ites have a backup argument -- the brand. It goes like this: "Apple makes awesome products, but even if they start being terrible, people will still buy i-devices for the logo."

Setting aside the circular reasoning, there's a very easy answer to the brand argument -- Research In Motion's (Nasdaq: RIMM) BlackBerry.

Remember, it wasn't too long ago that a BlackBerry was a CrackBerry, the "it" gadget that the iPhone is today. Fashion is fickle, and if your argument for Apple supremacy is based largely on its brand, you need a very good reason why iOS can't become tomorrow's BlackBerry, or bell-bottom pants.

The fog of war
Now, let's be clear. I'm not bashing Apple as an investment. I own shares myself. But, logic, not faith, should determine where you invest. History is littered with the bones of broken juggernauts cut down in their prime. There's no reason Apple can't join them -- particularly when you consider their future growth is built on conquering Asia.

Apple makes great products, but they're hardly untouchable. A lot of companies make cool gadgets, and one of them might eventually overtake Apple.

Ready to take a deeper bite into the Apple bear case? Check out our new report on "Why You Should Sell Apple."