The new Mac buying guide Adrian MI

Back in May, when we published our feature story "The New Rules for Buying a Mac", we tried to help prospective Mac buyers by tossing out the old rulebook and writing a new one, debunking lots of long-held myths along the way.

Now that the holidays are upon us, many of you might be considering the purchase a new Mac system. And in the intervening time, Apple has updated several of its models, particularly in its laptop line. (See our summaries of Apple's current Mac offerings.) So here's an updated set of buying tips based on the Macs that are available today.

The iMac: Power at a low price

For years, Apple's high-end Power Mac desktop systems were a great-and perhaps the only-choice for a wide variety of Mac users. Many Macworld editors, for example, would never have considered anything less when buying a new Mac. And when the iMac made its debut, it was an underpowered system that serious power users would never consider.

But things have changed. As the iMac entered the Intel era, something interesting happened: those lower-end systems became powerful in their own right, down to the dual-core technology that was previously the provenance of the highest-end machines. Now almost every Mac is suitable for general use, even by a wide swath of power users.

For most mainstay applications, the high-end iMac and MacBook Pro models are plenty fast for power users. Even Adobe Photoshop, a heavy-duty program that conventional wisdom has long argued should be run only on a high-end system, works acceptably well on just about any Mac (unless you're editing gigantic files).

Expandability: Do you really need it?

If you're a Windows PC user switching to the Mac, you may be frustrated by the fact that almost none of Apple's systems offer the upgrade flexibility that most desktop PCs do. You can upgrade a PC's graphics card, its hard drive, and even its processor and motherboard relatively easily. But on the Mac, those sorts of upgrades are much less common. You can't just replace a Mac's processor the way you can a PC's, there aren't as many Mac-compatible video cards out there, and Macs have never had the sort of "build your own" following that cheap PCs have.

For many computer users, expandability is a little like insurance. What if you want to add a hard drive? Or a new video card? Or more RAM? Or a faster processor? If your computer is truly expandable, you can theoretically stave off obsolescence with a series of canny upgrades over its lifetime. But most people don't really take advantage of their computers' expandability-especially the unique form of expandability the Mac Pro offers.

And these days, you can attach most peripherals via a Mac's USB, FireWire, and Ethernet ports-including speedy external storage devices and plug-in TV-capture hardware. It's extremely easy to install a new hard drive in a MacBook or MacBook Pro, and installing RAM in most Macs is also quite simple.

Running Windows on a Mac

Back in the PowerPC days, you needed a superfast Mac just to run Windows at painfully slow speeds via emulation software. One major benefit of Apple's switch to Intel processors is that now you can run Windows at full speed on any Mac, via Apple's free Boot Camp software.

However, if you want the goodness of OS X right alongside your favorite Windows programs, you'll need to use virtualization software, such as Parallels Desktop (; $80) or VMware Fusion (; $80). When you run OS X and Windows simultaneously, your Mac needs more power-and more RAM. In fact, we'd go so far as to say that your Mac's total RAM is a more important factor than the processor in running Windows virtualization software. (But the processor does help.)

That said, all current Mac models can run Windows fast enough for light to medium usage. Even the MacBook Air can run Windows decently, thanks to its 2GB of RAM.

If you spend a lot of time running Windows via virtualization software, you'll probably want a more powerful Mac, and you'll definitely want lots of RAM. To play cutting-edge 3-D Windows games, you'll need Boot Camp and a decent graphics processor-integrated graphics probably won't do the trick. But if you just want to run a few standard Windows programs on your Mac, you can choose any Mac, as long as it's got sufficient RAM.

Desktop or laptop?

In the old days, desktops had many advantages over laptops: more power; a better performance-to-price ratio; more expansion options; and the ability to have a large display, a full-size keyboard, and a mouse.

Today, Apple's Mac mini and iMac lines use the same "portable" versions of Intel processors and RAM as Apple's MacBook lines, so processor speed is no longer the deciding factor it was. It's true that Apple's desktop systems run faster than its laptops -- but not by much.

It's still true that you pay more for a laptop than for a similar desktop (a 2.4GHz MacBook Pro costs $1,999, compared with $1,199 for an iMac that has the same processor speed). Although the iMacs pack a lot of complicated electrical components into a small space, the MacBooks are even smaller, and they have to be built to conserve power because they must use a battery.

Cost aside, the only reason to choose a desktop Mac over a laptop is if you're never going to want to use your Mac anywhere but where you've parked it. If you've ever wished you could take your Mac with you, whether it's to your couch or across the globe, a laptop can give you flexibility that no desktop system can.

And when you do want to work at a desk, Apple's laptops can do that, too. All of Apple's laptops can drive external displays as large as 2,560 by 1,600 pixels-including Apple's massive 30-inch Cinema Display. And the 17-inch MacBook Pro's screen is so big that you might not even need to invest in an external display.

The same goes for input devices and expansion options. It's easy to connect an external keyboard and mouse via USB, or even wirelessly via Bluetooth (standard on every Mac), so you can have a full desktop experience with your Mac laptop. And the MacBook line's external ports (USB on all models, and FireWire 800 and ExpressCard on the MacBook Pro) can address most add-on needs, including storage and wireless data transfer.

The bottom line: Unless you're on a strict budget or you plan on using your Mac only at your desk, you can seriously consider buying a Mac laptop.

Two Macs or one?

If you share your home Mac with family members, they probably won't want you to take off with that Mac whenever you go on a business trip. But if you're a Mac's only user, it generally makes sense for that Mac to be a laptop. With a single system, there's no hassle with synchronizing data back and forth between a desktop and a laptop. At your desk, you can plug in to an external monitor, keyboard, and mouse, but you're still only a few cords away from complete portability.

So is a laptop that you can take on the road powerful enough to be your one and only Mac? If you need to take your Mac with you often, especially on airplanes with small tray tables and little personal space, a scale-tipping 6.8-pound 17-inch MacBook Pro won't be ideal. A MacBook or a MacBook Air makes for much easier transport, and with the latest revision to the MacBook line, the MacBook is more powerful than it used to be. But the 15-inch MacBook Pro, which is 1.2 pounds lighter and less deep and wide than its 17-inch sibling, can be a good compromise between power and portability.

Which Mac should I buy?

See all current Macs in our Mac Hardware Guide

For most people, even those who consider themselves power users, we strongly endorse the iMac. As Apple has improved the Mac Pro's specs, it has added features once considered "pro level" to the iMac line. If you've never considered buying an iMac, it's time to take a closer look at its dual-core processors, high RAM ceiling, abundance of speedy USB and FireWire ports, and support for external monitors.

We also strongly feel that potential Mac buyers should give Apple's MacBook and MacBook Pro family some serious consideration. With the Mac's transition to Intel processors, Apple's laptops have gained power they never had before-they work well on your desk and give you the benefit of portability. Not everyone will opt for a laptop, but a MacBook is all the Mac that many users will ever need.

[Jason Snell is Macworld's editorial director. Jonathan Seff is senior news editor.]