I've met a lot of people who had a Nokia 770 at the FOSDEM, and not surprisingly at the Maemo presentation made by Tommi Komulainen from Nokia in the Gnome room.
I spoke to the Nokia people, and was interested to know a bit more on how they conducted the project. They apparently faced the issue of making substential changes to the Gtk widgets (and other components of Gnome also) , which are not really interesting for most Gtk people, without willing to fork the codebase. The result is an ongoing process of trying to merge their modifications with the Gtk base. For sure, they are concerned with keeping in sync with the main codebase, to benefit of most interesting evolutions in Gtk. That's an interesting case to monitor to better understand the possible choices in such a situation.
We (at work) have more or less been confronted to that kind of situation, btw, on the ProGET project, where we have tried to submit most possible contributions to phpGroupware. We have published a paper on this subject : Why and how-to contribute to libre software when you integrate them into an in-house application ?.
Other informations I got at this presentation, is that they apparently are not willing to ship PIM applications : "we make an internet tablet", although it's possible to install GPE applications for instance, even if GPE is not as stable as the other tools Nokia ships today. Maybe this is why they don't consider this for now... Anyway, this is a bit contradictory to what one could imagine reading this linux devices recent article.
Also, it seems Nokia people are very much concerned about "Intellectual property" of everything they include in their products, and whith reasonable fear, considering the size of the company, which renders it lyable to so many others trying to sue it... This situation may not be the easiest for them since it may prevent users of their products to benefit widely from new inovations shipped by third parties.
Anyway, althoug not everything running on a Nokia 770 is Libre software, I am pleased to see Nokia trying to achieve productive and efficient collaboration with the Libre software communities, with the maemo project compared to what Sharp seems to be doing on their Linux-equipped Zaurus devices (i.e. nothing), which forces projects like OpenZaurus to have to reverse engineer most kernel drivers in order to provide an interesting platform for advanced users willing to enhance their machine.
Update : Michael Opdenacker has put online his recording of this conference. More details here.