Encryption is key
The only way I would consider a cloud-based solution is if it has solid encryption and only I hold the decryption keys. One example of this is TrulyMail. It's like email but a little different. The important thing is that my messages are only on their servers while they are encrypted, and they NEVER have my decryption key.
The idea of simply hosting a non-encrypted data store on someone else's server simply makes me too nervous. Although, I guess that what email is but I don't really like leaving my unencrypted email on someone else's server either.
Biting the hand that feeds IT
