I had a look at libchamplain. In fact i did that at the danish weekend as several people were asking for a map inside my tools since they weren't happy with the external usage of maemo mapper. Using clutter-gtk in the fremantle sdk isn't trivial and imho still doesn't work. At least i didn't manage to get anything into a usable state. I ended up using the osm-gps-map which provides lots of the functionality i am asking for.

I am sure there are many more of these things. Maybe you are correct that i should take a closer look at these. Still there's a difference in the quick-hack i could provide and something supported by nokia and actively promoted to be used in all kinds of applications.