De acordo com o fórum deles, o DropBox joga como um garoto de cinco anos mal-humorado em uma caixa de areia, ou seja, não tão bem:
http://wiki.dropbox.com/KnownIssues
OSX
Dropbox doesn't play well with FileVault: Spotlight won't find files in your FileVault locker including your Dropbox, if it's in the locker.
Solution: Move your Dropbox files outside of FileVault. They won't be encrypted (and you can't move them back in), but it's a temporary fix.
Alternative solution: You can teach Spotlight to index all files in your locker by adding your home folder to the list of files Spotlight should be prevented to index and subsequently removing it again. You can find the list under "Privacy" in the Sportlight settings in System Preferences. Once you added and removed the folder again, Spotlight should start indexing.
Dropbox doesn't sync until restarted for some users: No solution yet.
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