PHOENIX1701  Clearly it realized we were onto it and decided to exercise its better judgment and hide. Glad to hear things are working better! :)  
(Version 4.3.7284.3916)

PHOENIX1701  While Earth is hanging, try opening Activity Monitor, selecting Google Earth in the list, and choosing View > Sample Process. Paste the results into a reply to this comment (or at least paste the part that looks most relevant) and I'll see if I can suggest a culprit for you.  
(Version 4.3.7284.3916)

PHOENIX1701  Usually this sort of thing can be solved by deleting the Google Earth disk cache. If you can get as far as the preferences window, there's an option to delete the disk cache there. If not, though, you can delete the files yourself. They live in ~/Library/Caches/Google Earth/ and are called dbCache.dat and dbCache.dat.index. Hope this helps!  
(Version 4.3.7284.3916)

PHOENIX1701  Usually this sort of thing can be solved by deleting the Google Earth disk cache. If you can get as far as the preferences window, there's an option to delete the disk cache there. If not, though, you can delete the files yourself. They live in ~/Library/Caches/Google Earth/ and are called dbCache.dat and dbCache.dat.index. Hope this helps!  
(Version 4.3.7284.3916)

PHOENIX1701  The first thing I'd do is try nuking your disk cache. Once Earth is logged in, choose File > Server Log Out. Then go into Preferences, then click the Cache tab and click the "Delete cache file" button. Then log back in using File > Server Login. If the crash persists, try reducing the size of the memory and disk caches a bit -- I run at 500 and 2000 MB, respectively, and that works fine for me. If none of that works, consider posting to http://groups.google.com/group/earth-help with the problem; it's possible you'll find someone who's had the same problem before and fixed it. Good luck!  
(Version 4.3.7191.6508 )

PHOENIX1701  world28: in Terminal, run "otool -L /Applications/Cartographie/Google Earth.app/Contents/MacOS/libQtCore.4.dylib".

You should get output that starts like this:

/Applications/Cartographie/Google Earth.app/Contents/MacOS/libQtCore.4.dylib:

@executable_path/libQtCore.4.dylib (compatibility version 4.3.0, current version 4.3.4)

If the version matches (4.3.0), search for "libQtCore.4.dylib" and see if you find any other copies elsewhere on your computer -- it might be trying to use the wrong one. If the version doesn't match (i.e., if it says "compatibility version 4.1.0", then try re-downloading Google Earth and see if that helps.  
(Version 4.3.7191.6508 )