Take note kids: this is a shining example of how not to market such a large product/service change.
What a fiasco. Directly going against their About Page, failing to update their pricing page to indicate the change.. it's all bad.
I'm in the camp of everyone else where the TOS change is forcing my startup leave.
The net negative effect is that I'll likely start moving off of MailChimp for marketing emails as well. They've already broken my trust.
Their pricing model is a sham anyways: paying for list maintenance is utter BS. It's a small multi-kilobyte file if you're not actually using it.
I've taken to exporting and clearing certain lists at intervals to keep costs down. In reality, I should simply never have done user data collection with MailChimp to begin with.