Starting from the OSM snapshot 2011-05-25, eastern edge of the Western Europe region was shifted two degrees to the west to avoid overflow of the 4 Gb filesystem limit for memory cards.
For the same reason, starting from 2011-08-25, the eastern boundary was shifted one more degree to the west, i.e. to 13 degrees longitude.
Because of fast growth of the Western Europe maps, starting from 2011-09-21 eastern edge of the Western Europe region was moved to 11 degrees while Eastern Europe region Western extent is now 9 degrees longitude.
As a side effect, diff files for Western and Eastern Europe regions to update to 2011-05-25 are bigger than usually. With next update, they are expected to fall back to normal size.
