On http://maemo.org/news/ there is an item about a new site by ARM and (and Movial) that provides Open Source components, middleware and utilities used to build a Linux Mobile software stack on ARM. What made me curious was that the site apparenly offers "Application framework based on the GNOME Mobile Platform". Is anyone familiar with this? How does this compare to regular Gnome and Maemo?

Gnome Mobile, as far as I understand, should be something like a set of software stacks and technologies already popular with the Gnome desktop, bundled and optimized for mobile platforms. Actually, on their homepage they show the N800 as an example of devices using Gnome Mobile. This isn't wrong: Most of the components defined as the core of Gnome Mobile are what's used for Maemo (except for some like Avahi, IIRC).

avahi is used by the rtcomm beta iirc.

at least, i seem to have a avahi daemon installed on my N800...

But it's not in the stock OS. - At least I checked for it the day before yesterday (because I got excited about a post here claiming it would be part of ITOS2008) and was very disappointed to find out it's not there.

I actually was browsing around the documentation of maemo's overall layout and from what i've seen, Hildon is actually built on Gnome moble, witch is obviously whi most applications in maemo are gtk based and whi it uses matchbox as it's basic framework.
If you look at Gnome moble and Hildon, you can allmost edmeditly know whi thay include the N800 as a device that uses Gnome moble... Because.. basicly... If i am correct, Hildon is a form of Gnome moble that Nokia re-named and implimented into maemo. Their are a lot of similaritys between Gnome moble and Hildon.