By Aidan Malley

Published: 10:35 AM EST

Standing as the single largest change to an Apple portable in recent history, the 13" MacBook completely overhauls the system with a switch from plastic to a strong, thinner aluminum shell and a totally new platform that puts it into a new performance category -- albeit with key sacrifices to meet its goals.

Unibody design and the death of plastic

Without retreading too much of the territory covered in our MacBook Pro review, the new 13" MacBook represents one of the most fundamental rethinks of Apple's notebook design philosophy in several years and is an even greater change than for the professional-level models.

While still an important change, the MacBook Pro was already made out of aluminum and so has had many of the incidental benefits of using the metal format for years. It was thinner, often lighter for the size, and was resistant to everyday damage from scratches and stains. That wasn't the case for the regular MacBook, which has unfortunately had to contend with a plastic shell until now. It was relatively well designed; having used it extensively here at AppleInsider, though, it was clearly the definition of compromise. Plastic simply doesn't exude confidence. It creaks, it groans, and (in a few situations) could result in cracks and permanent discoloration. We just couldn't get excited about it.

Compared to that model, the new MacBook is a revelation. The unibody process, which inverts the construction from a "bucket" design that fills a bottom tray with contents to a single-piece case with two bottom panels, is absolutely rock-solid. Not once in our testing did the new model appear anything less than sturdy; and while it's not exactly a recommended carrying practice, you can even hold the notebook one-handed from a corner without the chassis giving the slightest hint that it's under too much stress. Apple obviously wants a system that will last for the long haul, and it just happens to look beautiful at the same time. It's Apple's best-looking and durable "starter" system ever, as far as we're concerned.



This structural boost includes the display, too. Despite being much thinner due to the uses of aluminum and LED backlighting, the housing for the screen is equally as sturdy as the shell and is actually more reassuring than the thicker plastic lid of the now-obsolete model. The hinge has been improved substantially as well and has a smoother motion with a wider possible angle than the old version. One caveat, however: the same mechanism that smoothes out the display's movement backwards also removes much of the resistance to moving forwards when the notebook is held near-upright, so those who tend to compute at extreme angles may find the display closing shut. It's a small tradeoff and definitely worth the benefits for the majority of users.

Heat appears to be improved: even while running intensive 3D benchmark testing, the MacBook merely got noticeably warm in the back-left corner rather than scaldingly hot as with earlier MacBook Pro units. Part of this may stem from the use of a cooler-running CPU, but the case and internals combined nonetheless result in a system which can actually be used as a laptop without a cushion or lap board to absorb warmth.

More impressively, Apple has managed to accomplish all this while slimming the MacBook down considerably from its plastic ancestor. The MacBook Pro again didn't have far to go; the new 13" system, however, is more than a tenth of an inch thinner than its outgoing equivalent and exactly a half-pound lighter. It's the first time in ages -- if ever -- that the company's consumer-level portable has been as thin as the pro system, and the reduced weight is better still than the much-loved 12" PowerBook's 4.6-pound casing. The aluminum MacBook feels tangibly lighter than either the old MacBook or the PowerBook, and that goes a long way towards wanting to carry the system everywhere.

As such, it's hard not to consider the unibody shell a massive step forward. There's an important and well-known concession in expansion that we'll touch on in detail further into the review, but it's hard to argue against the shift to aluminum and new internal construction given the strides in longevity and perceived quality. Most Windows notebooks, even those in a similarly high price range, just don't feel as well-built.