Ok I think I see some of it now. You can say that one object is only viewed at specific zoom ranges and that some of the vector art can be represented with something else at particular zoom levels too. So you can draw several maps of different scales and it will fade them in depending on the zoom and presumably change some markers into the full vector art at certain ranges.
The question I was asking was a little different but ill let it go for a while and maybe see it when there are some more demos. Its basically if at some zoom level you would use a certain bitmap for a city then is it possible to use another different FM8 map as that layer and thus be able to zoom into that map like a city with houses and everything. Ok lets put it this way. If one user of FM8 makes a city, can a different user put that city into a regional map so that you can zoom down to the house level.
For the record, ViewingDale auto generates all of the LODs with antialiasing and manages them for you and regenerates them if they change. It fades out small maps on a controllable global setting but not per object as objects can be reused at different scales. It also has a different optional setting for text only where it fades that out if its too big and therefore unreadable but not for objects, once big enough then it stays in. I could see why you might replace with an alternative but not entirely get rid of something there.
This is all very interesting and I am keen to see more of it and some different demos. Maybe a video of it running would be cool.