Engadget have published a lengthy interview with the big boss man, Reggie Fils-Aime.
One interesting point, the interviewer, Peter Rojas, asked if we should expect a third iteration of the DS in about 18 months time. Reggie replied:
"I wouldn’t say that that’s an unreasonable assumption. Look at how many times we’ve improved on the Game Boy Advance in terms of the look, the feel, screen changes, and everything else. We believe that type of constant innovation is critical to driving this industry, and certainly if you look at the world wide sales of Game Boy Advance, I don’t think anyone would disagree."
Reggie talks about all kinds of Nintendo related topics, Revolution, Zelda, DS and Gamecube. There's no stopping this guy.