Seeing as the 3500 is becoming their most popular drive it seems stupid (from my point of view, not the corporate greed machine) to force us into buying new technology that other vendors seems to be able to incorporate into existing drives.
Addmitedly Plextor hasn't got another drive higher than the 716A yet so they've concentrated on their most current drive, even Toshiba is adding faster DVD-R speeds via f/w and Lite-On has announced (but not yet delivered) a f/w upgrade for the 1663S to add 4x +R DL recording.
Are NEC so scared about straying from standards and tolerances that they have to design a brand new drive to implement features that other manufacturers seem to be able to implement via f/w into existing kit?
As has been mentioned, why implement faster DL speeds anyway if the cost of the media is still too high for most users? So far only Verbatim seem to produce reliable DL media so maybe the lack of competition keeps the price high?
So, could this f/w announcement by Plextor be a carrot to make people buy their drive