I believe your dropbox needs to be secure as your email account because it deals with storing your personal data.So offering 2 factor authentication is a step in the right direction, like what gmail has.
Other than that dropbox can't do much about people using the same passwords for different sites or social engineering attacks. You can educate and warn people about it, but it's ultimately up to the user to follow through.
Other than that dropbox can't do much about people using the same passwords for different sites or social engineering attacks. You can educate and warn people about it, but it's ultimately up to the user to follow through.