Lenovo continues to barrel into the PC market with sleek and stylish computers. This time, the focus is on thinness. Lenovo’s new IdeaPad U Series lineup of ultra mobile computers, which the company has dubbed “ultrabooks,” features the latest Intel Core processors and solid-state components. Are they the first real competitors to Apple’s MacBook Air lineup? Tech specs follow …

Three machines, the U300s, U300 and U400, are making their debut in Lenovo’s portfolio. The star of the show, however, is the U300s. Stuffed with up to 4GB of DD3, 256GB of SSD, a Core i7 CPU and a 13.3-inch screen, the .6-inch thick device is technically .08 inches slimmer than Apple’s 13-inch MacBook Air. (But unlike the MacBook Air, the U300s doesn’t taper down to .1 inch.) As with all of Lenovo’s products, it comes with the Lenovo Windows Enhanced Experience for fast bootup and shutdown. Couple those specs with the aluminum body (much like Apple’s MacBook Air) and you have yourself a truly beautiful PC alternative to Apple’s ultra-thin fleet of computers. Lenovo promises eight hours of battery life with the U300s, which is one hour more than what Apple offers with its 13-inch counterpart.

The U300 and U400 laptops offer similar ultra-portable designs, but with larger screens and screen resolutions and larger expansion options such as 8GB of RAM and 1TB hard disk drives. The U400 also includes the added bonus of a DVD drive.

The look and feel of the devices, including an all-aluminum body clad with a single rectangular buttonless touchpad complete with all black keys is very similar to Apple’s entire MacBook line of computers. That leads me to believe Lenovo is targeting users who may find Apple’s products appealing, but really need a PC for their day-to-day operations.

The U400 is highly attractive at the $849.99 price tag, especially when compared directly to the entry level 13-inch MacBook Pro. The U300s is starting at $1,199.99, which doesn’t compete against Apple’s $999 11-inch MacBook Air, but is exactly on par with the 13-inch MacBook Air. Users itching to get their hands on them will have to wait until November 2011.