I'm inclined to trust LiveDrive, Two reasons;

1) LiveDrive are a well respected, well known company with a good history of service and customer support. I use them as my main backup service (I never actually used Backify, just wanted to see what it was like) and trust them as such.

2) I just tried to log into my account and can't =)

If LiveDrives concerns about cards have some substance last nights message might have been a last ditch attempt at getting as much information as possible