“Apple finally has entered the subnotebook market, introducing a lightweight laptop meant to please road warriors. But, typical of Apple, the company took a different approach from its competitors. The result is a beautiful, amazingly thin computer, but one whose unusual trade-offs may turn off some frequent travelers,” Walter S. Mossberg reports for The Wall Street Journal.

“It’s impossible to convey in words just how pleasing and surprising this computer feels in the hand. It’s so svelte when closed that it’s a real shock to discover the big screen and keyboard inside,” Mossberg reports. “But there’s a price for this laptop’s daring design: Apple had to give up some features road warriors consider standard in a subnotebook, and certain of these omissions are radical. Chief among them is the lack of a removable battery. So, while the MacBook Air will be a perfect choice for some travelers, I can’t recommend it for all. It really depends on your style of working on the road and what features you value most.”

“In my tests, the MacBook Air’s screen and keyboard were a pleasure to use. The machine felt speedy, even with multiple programs running. And the laptop has the same Leopard operating system, superior built-in software, and paucity of viruses and spyware that I believe generally give the Mac an edge. I was able to install and run Windows XP using the third-party Parallels software,” Mossberg reports.

“But then there are those trade-offs. The sealed-in battery means you can’t carry a spare in case you run out of juice,” Mossberg reports.

MacDailyNews Take: There must be solutions for people trying to use an Air in ways it was not intended to be used, right? Well, you could carry an external battery for MacBook Air, which, we suspect, will soon become available. It’s pretty much the same as having to carry a second battery, except you’ll have to live with it not being stuck into the Air itself. If this is untenable, you’re probably more of a MacBook or MacBook Pro user.

Mossberg continues, “There’s no Ethernet jack for wired broadband Internet connections and no dedicated slot for the most common types of external cellphone modems. That means that out of the box, the MacBook Air has only one way to get on the Internet — through its fast, built-in Wi-Fi connection. If you’re out of Wi-Fi range, you’re out of luck, unless you buy an optional, $30 add-on Ethernet connector or a cellphone modem that connects via USB.”

Mossberg writes, “That single USB port is a problem, because so many peripherals use USB. You can buy a tiny, cheap USB hub that adds three more ports, but that’s yet another item to carry.”

MacDailyNews Take: So, it’s not really much a a problem at all. If a tiny, cheap USB hub is untenable, you’re probably more of a MacBook or MacBook Pro user.

Mossberg continues, “In my standard battery test, where I disable all power-saving features, set the screen brightness at maximum, turn on the Wi-Fi and play an endless loop of music, the MacBook Air’s battery lasted 3 hours, 24 minutes. That means you could likely get 4.5 hours in a normal work pattern, almost the five hours Apple claims.”

Mossberg writes, “If you value thinness, and a large screen and keyboard in a subnotebook, and don’t watch DVDs on planes or require spare batteries, the MacBook Air might be just the ticket. But if you rely on spare batteries, expect the usual array of ports, or like to play DVDs on planes, this isn’t the computer to buy.”

More in Mossberg’s full review here.

[Thanks to MacDailyNews Reader “Too Hot!” for the heads up.]

Just as Apple’s Mac Pro is not designed to serve the entire desktop market, Apple’s MacBook Air is not designed to serve the entire portable market. However, if you’re intent on trying to convert a MacBook Air into a thin pseudo-MacBook, read on:

If you rely on spare batteries, wait a bit for the external batteries to debut. If you expect the usual array of ports, you’ll want to invest in an inexpensive USB travel hub and an Apple’s USB 10/100BASE-T Ethernet Adapter (US$29). You’re out of luck on the FIreWire front. If you like to play DVDs on planes, you should really consider dumping the battery-draining practice of spinning shiny discs and play movies off your drive (internal or external; for example, an iPod in Disk Mode) instead. If any or all of that fails to work for you, you’re probably more of a MacBook or MacBook Pro user.