I still don't see any way to use this without major changes to Article 324 or a new article. The rules in 324 only permit it to be installed under carpet squares and do not permit it to be used in residential applications.
Don
Don, you are correct in the sense that it won't be Article 324.
Here provided is a link to an Analysis of Changes, NEC-2008. Scroll down and read Article 382, which I will quote below the link for convenience. Note the figure 7 image is 120v FlatWire.
http://www.iaei.org/subscriber/magazine/06_e/johnston.html"... New technologies, consumer electronics devices such as flat panel televisions and custom audio systems, along with ever-changing lifestyles have increased the need for additional power outlets and the desire to place power or lighting outlets where needed to obtain functionality as well as an aesthetically pleasing environment. Often these changes are poorly accommodated through the use of extension cords that are easily damaged, misused and can lead to electrical hazards. This new type of concealable flat nonmetallic extension incorporated into Article 382 provides a safe and reliable alternative for existing occupancies that can reduce the misuse of extension cords, overload power taps, and so forth (see figure 7)."
"Article 382 has been revised to incorporate provisions for concealed flat nonmetallic extensions. A new definition of this type of concealable flat nonmetallic extension has been added in 382.2. The article has been expanded to include specific product listing requirements in 382.6. Sections 382.10 and 382.12, covering Uses Permitted and Uses Not Permitted, have been revised and expanded to incorporate requirements and restrictions for concealable flat nonmetallic extensions. A new Part III has been added to Article 382 and provides specific construction specifications for concealable flat nonmetallic extensions."