Google Maps has been subtly improving while I wasn't looking. There's now at least nominal low-resolution outline map coverage of the whole world, though real coverage still seems limited to the US, Canada, the UK and Ireland (though Satellite covers some other places at high resolution, such as Sydney, Australia). I'm also amused to see that they seem to have partly followed my suggestion and switched the map view to a Mercator projection, though the Satellite view is still on a raw latitude/longitude grid.
Though Mercator is famously
EVIL! as a projection for a world map due to its extreme distortions of relative scale, it's probably about the best you can do if you want a seamlessly
zoomable and
pannable flat map covering the world, since a magnification of any small part of it is guaranteed not to look squashed. Google Maps seems curiously unconcerned with scale anyway, except for distances on driving directions. To do much better you'd have to go beyond Flatland to something like
Google Earth that can reproject the map dynamically.
The zoomed-out view of the whole United States also seems to identify the major cities a little better. Interestingly, I had to update the
Google Maps Dashboard widget to see the new versions of the maps in it; I guess they changed the API somehow.