I use the same email for my Google, Facebook and Twitter accounts.
However I can only log in to my imgur account via Google and Facebook, not Twitter.
I realize that it sounds kind of dumb, but I am a bit OCD about my social network services and such; I like them to be all connected. Never mind if it is demanding. Just thought I'd share what I wanted :D.
Thanks for having a great service even if this doesn't get implemented.
Customer support service by UserEcho