I moved my site's database to RDS a few months ago. At the time, I finally decided I was ready to have a dedicated database server, and during the process of setting one up on EC2, I discovered RDS. I've been really happy with it.
The problem is this: While I understand that Amazon is running great backups of my database, and I'm excited about that, I don't feel good about having all my eggs in one basket. Because RDS won't give you access to the binlog, I'm not sure how/if it's possible to back up elsewhere - I'd like to keep a backup on an entirely separate service, and I'd like it to be as up to date as possible.
It sounds like read replication to a server outside of AWS is out of the question (but correct me if I'm wrong there). Do I have any options?