I've had a Tumblr weblog for quite a while now and all of a sudden MarsEdit cannot log in to the account. I deleted the weblog from MarsEdit and tried to add it back. MarsEdit can discover the weblog address, but I get the Login dialog over and over and over.
I even went to Tumblr to see if I was using the wrong email address and password. I was using the proper address and password.
I have a feeling this is something on Tumblr's end. I'm headed there next.