AmazonSES is Amazon's Simple Email Service (or something like that), which Dreamwidth and a lot of other sites use for sending large volumes of email. It's generally pretty reliable, though, and if it was affecting everyone using Amazon's cloud services and SES, we'd probably hear about it more widely.

It's confusing. Could the Google forum people be looking just at the last attempt, and not seeing the earlier attempts that got greylisted and delayed, because only the last one is coming through?