That's a bit too much like a loyalty penalty for my taste: the default option makes things better for new users than for established customers.
(Of course loyalty penalties are commonplace -- from phone companies, car insurers, etc. -- but my mental model of cperciva says he probably doesn't like them.)
my mental model of cperciva says he probably doesn't like them
Exactly true. I was looking at that comment trying to put my finger on why I hated the idea so much, and you're right: It's because it would be a loyalty penalty. I want to be fair to everyone.
As a customer of about 2 years now, it is much appreciated. I feel much better doing business with corporations when I get the feeling that they do their business fairly. Tarsnap succeeds at this.
"we are thus launching a new price layer at .25, new users will be automatically enrolled in this one and you can switch by doing X"
This way people who want to actually donate more, or do not have enough of a preference would still give you more money.