Just fishing out the api keys is a feat in and of itself. Then there's like what, 3 to 5 different ways you can set up a mailing list, all using slightly incompatible methods/datastructures/layouts/whatever. By the way, I'm calling it a mailing list because that's what they are. But mailchimp has different unique terminology for each way. And that's just the tip.
MailChimp was great until it wasn't. I decided to use aweber for my last project after previously using MailChimp to manage over 100k subscribers.
That said, I highly respect the fact they've been bootstrapping. And I don't that bootstrapping has anything to do with the lousy choices made after they reached significant scale. You can't win them all.
