** Updated 2013: Obviously, this was too late to save Nokia **.
To some, including me, the [Nokia N900 beats the Apple iPhone (http://thenextweb.com/2010/01/03/nokia-n900-takes-6-stabs-iphone/), at least for technology aficionados, a.k.a. geeks. While a tribute Apple's innovative leadership, it takes a company with Apple's innovation and Jobs' experience to base some products on open-source and keep the bulk closed-source - the 20/80 route.
Nokia has taken the 80/20 road in its approach to open-source and the Maemo mobile OS. It actively integrates with upstream packages for the core layers, while contributing generously back to the community. In the mobile arena, the development of affordable mobile hardware requires control over a few aspects, and then the organization that provides the discipline can make money through brand differentiation, user interface and customer support, among other services -- the 20% in the Nokia-Maemo case.
This model is approaching the relationship of some pharmaceutical companies to base-research academic institutions. The research and theory is relatively open, and then the testing, branding, sales and support is the commercial activity.
OK - back to the N900 - which is a fabulous device, and works in almost the same way as my Ubuntu desktop works: packages from the main vendor, and then third-party repositories, and my own hacks, all working seamlessly. No jail-breaks, no contracts, no carrier tie-ins -- a freer world and if Nokia manages to make money which I think it will -- considering that the phone is still on back-order three months after release, it would be a validation of the maturing open-source model for commercial companies.