Just because Macs have ended up taking a back seat to Apple's (Nasdaq: AAPL) iPhones and iPads, that doesn't mean investors should blow them off.

Last quarter, Macs (including desktops and laptops) contributed just 14% of Apple's $46.3 billion in revenue, which hardly compares with the 72% that came from iPhones and iPads combined. Within Macs, laptops are far more popular than desktops, accounting for 71% of Mac revenue. Apple sold more than 2.5 times as many laptops as it did desktops in the quarter, making its various MacBook families incredibly important to its traditional computer business.

Back to the Mac
When it comes to the MacBook Pro that's geared toward the, um, pro market, the last time the family saw a major redesign was in 2008, when Apple transitioned to its sturdy unibody construction. The Mac maker is now widely expected to dramatically revamp its MacBook Pro lineup this year with a significantly different form factor that will probably take many design cues from its incredibly popular MacBook Air family.

Source: Apple.com. MacBook Air.

Apple even directly hinted at this distinct possibility when Steve Jobs unveiled the redesigned MacBook Airs at Apple's "Back to the Mac" event in October 2010. "We really see these as the next generation of MacBooks," he said. "We think all notebooks will be like these someday." Not so subtle, right?

"They've done studies, you know. Sixty percent of the time, it works every time."
A classic clue that an upgrade is imminent for any Apple product is that its supply distribution to authorized resellers begins to dry up without explanation.

This exact phenomenon happened just over a month ago, when supply of the Apple TV set-top box, or STB, started seeing shortages at retailers such as Best Buy, Target, and Amazon.com, among others. Apple then promptly refreshed the Apple TV STB alongside the new iPad, adding in 1080p support for HD content and some improved specs.

Now we're starting to see shortages for various MacBook Pro models at third-party resellers, which strongly hints that an upgrade may be within weeks.

What to expect when you're expecting new MacBook Pros
Apple doesn't always hold media events for Mac upgrades, but it sometimes does when they're big updates, so we might see some press invites go out relatively soon if Apple decides to host an event. Regardless, what can we expect in these new machines?

More than likely, Apple will ditch the optical DVD drive as it's been quickly transitioning to digital distribution for content and software. It even used its Mac App Store as the primary distribution method for the last major Mac OS X upgrade, 10.7 Lion. It's almost guaranteed that Apple will move toward all-flash storage also.

Intel's (Nasdaq: INTC) latest Ivy Bridge processors are due out now, which will move down to a 22-nanometer manufacturing process and improve integrated graphics performance. These new chips are basically guaranteed to be featured. New iMacs with these processors are expected this summer.

Speaking of graphics, a big toss-up will be if NVIDIA (Nasdaq: NVDA) won back its discrete GPU spot from Advanced Micro Devices (NYSE: AMD). NVIDIA's new Kepler architecture, based on a 28-nanometer process, has a good chance of making an appearance -- although yield issues at Taiwan Semiconductor Manufacturing (NYSE: TSM) may hold back how many seats NVIDIA might have.

Apple is also definitely interested in boosting the resolutions on Macs, as evidenced by ultra-high-resolution "Retina" images buried in the OS. Dubious Digitimes has previously said these "Retina" MacBooks are due out in the second quarter; this is a definite possibility but remains another big toss-up.

Wait for it ...
This update is bound to be a big one -- the most significant in four years. There are still a few unknowns, and a Retina MacBook could be a total game-changer for the industry. Anyone who's out there that's in the market for a new MacBook Pro should hold off for a few more weeks if they can, because it'd be a shame to miss this one.

Either way, these newest models will be a major Mac catalyst for Apple, and it's probably just around the corner.

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