I have a question. I noticed when zooming out it can change the type of road. In this case it changes from a highway=tertiary to a highway=primary. Are there different roads defined on different zoomlevels:
The map tiles for different zoom levels are not all updated at the same time.
Usually the lower zoom levels are updated less frequently. Because they require more processing etc, and they change less often.
It looks like those road were tagged as motorway, but were changed to tertiary a month or two back. And not all of the tiles had been updated.
Note there is a way to get tiles to be rendered by marking them as dirty. See this page for instructions: http://wiki.openstreetmap.org/wiki/Slippy_map
I have now done that for that zoom level 12 tile, and it now looks correct.