Can’t get enough of those super-slims.

There’s no formal criteria for what puts a PC notebook into the “super-slim” category, but I’d suggest that it needs to weigh no more than 3 pounds, more or less, and have a thickness of no more than an inch.

Asus and Dell, both champions in the lighter/slimmer quest, have announced new machines that more than qualify as super-slims, which now seem to fit a niche somewhere between the netbook and the conventional notebook. Pricewise, they generally cost as much or more than either of those varieties.

The Asus UX30 is currently on sale in Japan in a 3-pound aluminum body, selling for about $1,100 and running Windows 7 under the power of an Intel Core Duo processor. The profile of the machine is .77 inches, which is thin under anyone’s definition.

There’s only a few silly millimeters that separates the thickness of the Asus and the new Dell Vostro, but that’s like carving tenths of a second off the zero-to-60 times of a sports car.

The $450 Vostro V13 borrows from the Adamo XPS, but deletes much of the Adamo’s sex appeal. It measures .65 inches thick—the Twiggy of computers—and options a couple of low-voltage Intel chips up to a Core 2 Solo, plus adds an eSATA port, among others. Dell has since confirmed that the Vostro V13 is on sale worldwide.

With the annual Consumer Electronics Show creeping up and set to go just after New Year’s, many electronics companies are offering the press some sneaks into their marketing futures.

Consumers can expect a range of ultra-slim devices from companies like Sony, Lenovo and Dell, some new “green” computers, a few “ultra netbooks” that slot below the current models, and new Intel processors, including the advanced Pineview chip for netbooks.

Speaking of those, some manufacturers are concerned about the rates of return by netbook customers; seems that living with a small screen, and without an optical disc drive, can be a challenge. (NYT)