Unfortunately SES servers seem to be regularly blacklisted. A quick google confirms. I've been using SES for 3-4 months now and had a few hard bounces with specific mention to the IP being banned.
actually I never had blacklisting problems on aws ses.
My guess would be that the big providers ignoring the blaklists for themself.
I mean even Google sometimes gets on a blacklist or Microsoft on still no email happened to be in Spam filter.
