Tourism New Zealand and Google have recently announced the addition of a new layer to Google Earth. It can be found under Layers > Travel and Tourism > 100% Pure New Zealand. I hope that this is the start of a long term trend towards greater availability and publication of public geospatial data.
The key issue here is probably going to be the adoption of an OGC standard for publishing this information - hopefully Google will release KML to the OGC for this purpose. Organisations wishing to publish there geospatial data in either web-based 2D or virtual earth 3D applications should only have to publish the data in one format, rather than using a different format for each vendor.
I have personally being asking for the likes of bus routes to be made available in Google Earth as a means of starting organisations thinking about going down this path. I'm hopeful that this move by Tourism New Zealand will prompt greater consideration and action in this arena.