I think this is amazingly great. If they can compete with AWS SES on pricing then, why should I work and pay to 2 services if I already use cloudflare and just use AWS SES for transactional emails. BUT and this is a big one. Most OSS already integrates with SES, so I doubt it will be easy to replace, it may take years, unless.... they can replace them completely as is without adding new codes and apis...