Iterative and incremental development ideas have been presented for general new product development (NPD) for years. I'm interested in agile methods (as in software development context) because they give a philosophy behind and lots of ideas how to actually do this. It is of course also because of extremely active and powerfull community. Ideas of using these methods and practices in NPD in general have been presented by Jim Highsmith (Agile Project Management), Preston G. Smith (Developing Products in Half the Time), and many more. Both of above mentioned can be contacted via Cutter Consortium.
Now there is something new coming up. At London Agile Business Conference 2006 few weeks back the DSDM consortium talked about the future of the DSDM framework. DSDM version 4.2 has been open for online viewing since this year. They are going to publish a new version of framework in Spring 2007. This new version is supposed to be more general and not specifically targeted to just software development. It was also presented that DSDM can be seen as a wrapper for models like Scrum and XP for use in enterprise environment. It's a bit too structured to my tasting, but very well worth to check out when available. It may also become more open.