Other than ec2, what AWS services were you using and how did you migrate those? At minimum, I'd guess you were using elb for load balancing, sqs for queues and elastic cache for redis.
We are still a loyal customer for some of their services. For example, we still use S3 for off-site backups and Route53 is still our primary DNS provider.
For load balancing we have moved to a Route53 (health checks and round-robin) + a group of nginx+haproxy+lua-based frontend boxes.
Everything else was either built in-house or used open-source components and wasn't really tied to EC2 infrastructure.
