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Dan, you asked:
"So what are some of these details?  Particular undersea seamounts?
Particular depths that are commonly wrong?  Can you share a few
specifics?"

Lots and lots of things! The Tongue of the Ocean in the Bahamas is properly 
defined. This has been a mess in many digital mapping products ever since a 
little database called "ETOPO5" was released over fifteen years ago. I have 
always considered this a good case study of digital mapping taking a step 
backward from traditional mapping. These waters have been known for 
centuries. It's nice to see that the digital world has finally caught up.

Take a look at the shoals southeast of Nantucket. It's hard to find that level 
of detail displayed correctly anywhere. The global coverage is spotty, as is 
also the case with the aerial photography in Google Earth. So, for example, 
the English Channel is rather barren, but the canyons off Monterey, 
California are beautifully rendered.

Adding depth data has clearly caused some problems. Try zooming in on the 
Isles of Scilly. You can see them on the high altitude map (where much of 
Cornwall is still on-screen), but as you get closer and closer, they fade and 
then disappear beneath the waves. Oops. Also, I wish they offered more ways 
of viewing the data. It would be nice to see the bathymetry keyed directly to 
depth rather than displayed as shaded relief, like topography. Maybe that's 
possible and I haven't figured out how...

The Google folks have not yet incorporated depth data for most inland bodies 
of water. The Great Lakes are blank. So is the Caspian Sea. The Black Sea is 
rather poor. Depth data is available for these. It appears that Google Earth 
simply hasn't acquired the data yet.

-FER
PS: I warn you; it's very addictive. Enter at your own risk. 




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