According to Laptop Magazine, the standard battery has been upped from 4- to 8-cells (previously a $99 option), the keyboard "no longer acts like a trampoline", and the price has been dropped $100 (now $799) to boot. Core specs (Core 2 Solo SU3500 CULV, 2GB RAM, 320GB) remain the same.

Of course, the battery adds a little extra heft, but with the current 4-cell model being sold at about $749, the update seems like a decent deal. [Laptop Magazine]

First, let's focus on what the X340 gets right. It's a 13-inch (16x9, 1366x768) laptop that weighs just 2.86 pounds with its 4-cell battery. It measures .78 inches at its thickest point and .24 inches at its thinnest. (The MacBook Air measures but .76 inches at its thickest point and .16 at its thinnest.) In real life application, the X340 seems a tad bulkier than specs might reveal because the tapering isn't as dramatic as the Air's. But it's still thin.

The 1.4GHz Core2 Solo processor is quite a bit faster than your average Atom, and its HDMI I/O port and draft n Wi-Fi are a welcome addition to such a tiny machine.

OK, now for the bad stuff.

The keyboard feels dreadful. Not only are the keys...mushy...the center of the keyboard literally bends while you type. It's frightening to watch and extremely disconcerting as you wonder if they next keypress will greet your fingertips with a charged circuit board.

As for the remainder of the machine, it doesn't feel much better. The only way to describe the plastic body is "cheap." Not only does the glossy black finish reveal a strange, flecked iridescence under light, tap on the palm wrests with your knuckle and something about the hollowness of the pitch assures you that it could easily crack under a moderate amount of pressure.
Molding the trackpad into the case...that was a bad idea. The surface simply doesn't feel lacquered as a working trackpad. Literally, it feels unfinished, like someone on the assembly line went on break instead of gluing on the proper touch sensitive rectangle.

When you hold the Air, it's an incredible sensation not just because of its size but because of how sturdy it feels at its size. The X340 misses the pleasure of this dichotomy and gives us what I'm willing to wager is the most fragile laptop I've ever put my hands on.

Performance
Believe it or not, while the X340 is burdened by Vista's heavy footprint, it's quite usable. General navigation seems infinitely faster than running Vista on a true netbook, like the Dell Mini 12. The benchmarks support the fairly fluid experience of the OS.
The X340 is clearly closer to a netbook than the MBA in performance, but that performance gap between netbook and X340 is definitely noticeable in your general day to day experience of loading apps.

The X340's graphics chip is the Intel GMA X4500MDH. All you really need to know is that this architecture is nowhere near as good as NVIDIA's 9 series stuff, like the 9400M. And it's not powerful enough for heavy gaming (the 9400M is already scraping the barrel pretty hard). You can see the two platforms side by side here:

Still, MSI claims that the system can handle smooth 1080P playback. Can it? In a word, no. Neither HD web content (like Vimeo) nor 1080P MPEG4 played back smoothly on the system. The Blu-ray quality MPEG4 probably never broke 15fps.

In reality, the X340 performs up to most of my expectations (since I never believed it could handle 1080P clips anyway). Just don't expect it to be some sort of dream multimedia machine. In that regard, the X340 is like a netbook on steroids—fine for general use, just not juiced up enough to handle the next tier of graphics-intensive operations.

The battery lasted 1 hour, 43 minutes - ouch*
You could probably stretch the life beyond two hours with a few tweaks, like gimping the processor or squinting at the screen, but if you're planning on watching a movie during your next flight, it'd better be from the 90-minute Pauly Shore Archives.
*MPEG 4 playback, Wi-Fi on, screen at full brightness, "balanced" performance. You can purchase an 8-cell battery that should hit 3 hours for a bit more weight

The Sad Conclusion
I should be thrilled with the X340. It's lighter than many netbooks that have smaller screens. While not as tailored as the MacBook Air, hey, it's damn close. It also runs Vista at a reasonable speed.

The problem is, I just can't look at this machine, as thin and light as it may be, and feel good about dropping nearly $1000 to make one mine. If the X340 were much cheaper (unlikely) or sturdier (quite feasible), there's a good chance I'd be thrilled in this review. I just can't imagine showing this machine off to a friend, or getting extreme satisfaction when pulling it out of a bag. And if I've lost those attributes, I might as well settle for a somewhat thin full-blown laptop for less money, or a very light netbook for even less money.

But if you're looking purely for the lightest way to fit a 13-inch screen into your bag that's waaayyyy cheaper than the Air, and you only want to use a computer for 1 hour and 34 minutes at a time, then I'm not stopping you.

Extremely light and thin form

Runs Vista adequately

Short battery life

Weak for multimedia applications

Unreasonably poor build quality

[Additional research from Geekbench]

X340 feature the HD LCD! Is among first notebooks to utilize Intel's CULV CPU!

CITY OF INDUSTRY, CA is excited to release the full specifications! The new Wind U123 and the X320 & X340 X-Slim Notebooks model offer features the new processor.

The Wind U123 offers users an ergonomics designed keyboard and touch pad for comfortable!!

Typing and an enlarged 10.2" LCD display are perfect for browsing without.

Squinting MSI also included EasyFace identification software to protect confidential data and for the first time. Offering the Wind in blue and red in addition to the standard white and gray colored models.

U123
Intel® Atom™ Processor 1.66GHz (N280)
Windows XP Home
Intel® 945GSE + ICH7M
Intel® UMA GMA950
1GB DDR2 533MHz ( One expandable memory dimm slot )
10.2" WSVGA (1024 x 600) LED
160GB / 2.5" SATA HDD
4 in 1 (XD / SD/ MMC/ Memory Stick)
D-sub x1, USB 2.0 X3, Mic-in, Headphone RJ45 , TV Antenna Connector
6 Cell/ 9 cell (Optional)
802.11 b/g, b/g/n, Bluetooth V2.0EDR
Dimensions 10.24" x 7.08" x 0.38"~ 1.30"
Weight 2.98 lbs with 6-Cell battery

X320/340
Intel® Atom™ Z530 1.6GHz Processor Intel® ULV™ SU3500
Windows Vista Home Premium
13.4" (Glare / 1366x768)
8.8"(L) x 12.9"(W) x 0.7"(H)
2.8 lbs with 4-Cell battery
Intel® US15W Intel® GS45+ICH9M-SFF
Intel® GMA500 Intel® GMA4500MHD
DDR2-667 up to 2GB DDR2-800 up to 4GB
250GB / 2.5" SATA HDD 320GB / 2.5" SATA HDD
LAN 10/100 Gb LAN Gb LAN
Wireless LAN 802.11b/g/n 802.11b/g/n
Connection 3G / WiMAX (Optional)
Battery 4 Cell/ 8 cell (Optional)

The sub-3lb system toured in this clip is loaded with an Intel Celeron M 725, which should be faster than an Atom. The 15.6-inch version comes with a Core 2 Solo. More about 'em both here.

Those of you who speak German will probably mind the incessant slurs intended to offend American audiences, but luckily, I don't speak a word of it so I was able to enjoy the mechanics of battery removal with no guilt for enjoying my sausages on a bun. [via CrunchGear]