MacBook Air vs. MacBook Pro: Which Apple 13-incher should you buy?

(Read our new head-to-head buyer's guide for an updated comparison between the 2012 13-inch MacBook Pro and Air.)

Just a few short months ago (in March, to be exact), we wrote about an odd glut in Apple's otherwise streamlined lineup of products: instead of one or even two 13-inch laptops to choose from, Apple was offering three. The white MacBook, the MacBook Air, and the MacBook Pro each had a slightly different value equation in terms of design, features, and price.

That glut's been lessened a little now that the white MacBook has been discontinued. The MacBook Air and the MacBook Pro are the only two MacBook product lines left, and they represent two different solutions to same problem. The unibody aluminum Pro used to be considered thin, but it's--relatively--thick at 1 inch, and weighs over 4 pounds. The Pro offers better specs, while the Air, which has just been recently updated, leans toward light weight and quick booting as its advantages.

There's more to consider, though: the 2011 13-inch MacBook Pro and new 13-inch MacBook Air have become more similar than they've ever been before, for several reasons: performance, battery life, and a Thunderbolt port.

Two 13-inch MacBooks: which do you choose?

Let's put them side by side and compare. (Note: For additional price-based consideration, we're throwing the higher-end 11-inch Air into the chart comparison, since its $1,199 price matches the entry-level 13-inch MacBook Pro.)

Size: How quickly things change: in March, the 2011 MacBook Pro was the newest laptop in Apple's stable. Now, it's the oldest. It's obviously far heavier than the 13-inch Air, by over a pound and a half. Edge: Air.

Performance: Last time, we recommended the entry-level 13-inch MacBook Pro as the best all-around Apple 13-incher in terms of price, design, and performance. The MacBook Air has caught up fast. Its price and base RAM/storage specs are still the same, but the new Air has a dramatically faster second-gen Core i5 CPU that makes for a far better computer. Benchmark results are so close they're practically indistinguishable: despite the Air having a lower-speed CPU, it performs nearly identically to the Pro. The 11-inch Air's no slouch either, and it's nearly as good, its performance lag likely being due to having less RAM and a .1GHz slower processor. Edge: Tie.

Battery life: Again, nearly the same. The MacBook Air lost the battle in the spring, but the new, more power-efficient second-gen Intel Core i5 CPU has evened the comparison. Both 13-inchers netted around 6 hours and 40 minutes. Edge: Tie.

Extras: The 13-inch Pro wins on features, but it's a narrower win than you'd expect. A larger hard drive and a DVD-burning optical drive are the larger Pro's advantages, along with an HD Webcam. Port-wise, the Pro adds a FireWire port and an Ethernet jack, and that's it. However, the Air has a higher-resolution 1,440x900-pixel display, while the Pro, oddly enough, has a 1,280x800-pixel screen. Edge: Pro.

And now, case by case:

Best value for the money: Pro. Unless you truly value size and weight above all else, the 13-inch Pro offers more features, ports, and hard-drive space, along with an optical drive. The advantage is narrow, though; narrower than it's ever been.

For the coffee-shopper and frequent traveler: Air. Obviously, size is key. The Air's tiny, and now it also has improved battery life. Some people, though, might prefer the even smaller 11-inch Air, although it doesn't last as long on a charge.

Student who wants to save money: Pro. Last time, we said to get the white MacBook, the king of value. You're out of luck on deals this time. The $999 11-inch Air is the cheapest, but sacrifices valuable storage space. The $1,199 Pro's technically a good value, but more expensive. Educational discounts currently have the entry-level Pro at $1,099 and the entry-level Air at $1,249. Does a difference of $150 affect your purchasing decision? Alternatively, perhaps consider the $499 iPad, or a Windows laptop.

Money is no object, best computer: Air. We would have said the 13-inch Pro a year ago, but you might as well consider splurging on a 256GB 13-inch Air with an upgraded 1.8GHz Core i7 processor, and get a Thunderbolt-connected storage array along with a Thunderbolt Display to dock with. It'll cost a fortune, but you said you were rich, right?

Executive with expense account: Air. See above. The MacBook Air is finally as fast as the 13-inch Pro, so there's less of a sacrifice between size and speed.

Conclusion: Very tough call. Now it's a split. We give it to the 13-inch Pro on a technicality, for now, for the average person looking to replace an everyday laptop. The 13-inch Pro is still a bit more of a value, even though the Air is arguably a better pure portable Mac. The Air did earn an Editors' Choice Award on CNET, whereas the 13-inch Pro didn't, but that's also a matter of accomplishment for its size class: the 13-inch Air is the best thin MacBook, while the 15-inch Pro is technically the better larger-form MacBook. Even though Apple's Web site suggests that new users start with the MacBook Air, technically, if you're considering a 13-incher, you should start with the $100-cheaper 13-inch Pro.

Are an optical drive and extra hard-drive space worth the added weight? With networked hard drives, external peripherals, and cloud-based storage, is the 13-inch Air more your style? Sound off below, let us know what you'd prefer.