Despite the drawbacks mentioned by Apple’s Cook, netbooks are the fastest-growing segment of the notebook computer market, and are starting to draw the interest of .

But a Mac OS-based, multi-touch “nettablet” would be an entirely different animal. And it would be a way to make Apple’s growing investment in its “mobile computing franchise” pay off, according to a research note prepared for clients by Piper Jaffray’s Gene Munster, with other researchers. This investment priority is evident, according to Munster, based on information gleaned from Asian component suppliers, recent Apple patents for multi-touch technology “for more complex computing devices,” recent comments by Apple’s Cook, the acquisition of , and recent chip-related staff hires.

A Mac tablet, even with a relatively small touchscreen, would offer the kind of technological distinctiveness that’s an Apple hallmark, the report suggests. Munster conceded that the component vendors on whom he relies have not seen any prototype touch tablets. But the adds that Munster says these vendors have been in discussions with Apple about the parts needed to build one.

“For his part, the analyst believes the device will end up retailing somewhere in the range of $500 - $700, bridging the gap between the $399 iPod Touch [an iPhone without the cellular modem] and the $999 MacBook,” according to AppleInsider.

The even thinner, sleeker MacBook Air shows the kind of compactness and lightness Apple might be able to introduce in a small touch-based tablet, though the Air comes with a very high premium, starting at $1,800.