I don't read German, but sounds like a lot of speculation and conjecture based on what I know about the platform. Devices are supported for a minimum of two release cycles (i.e., Maemo 4 and Maemo 5). If Fremantle is released and doesn't support the N810, then the N810 will have only had one release cycle (even if you take Diablo as its second release, the N810W will still have only had one).

Fremantle is definitely shipping before 2010, and Fremantle will be bundling Qt, so that claim seems unlikely, andeverything that I've heard so far about Qt has been as something shipped alongside GTK, but not replacing it (this was definitely the tone at LinuxTag), so I'm not sure I buy that, either.