This is easily done with Elastic Load Balancers, simply proxy to different ports for SSL and instruct your webserver to listen there. The huge upside is you can automate this just as well as any other piece.
Of course, you can just setup your own load balancer on EC2 with HAProxy and stunnel, but that's a PITA.
and PITAs add complexity and cost.Using ELBs is the best solution, but it's a non-issue if you go dedicated.
The issues I was considering with la nuebla:
Data is a pain. S3 is great in theory but a pain to integrate. The same goes for EBS, which is really pricey for more than a little. If you can get a good connection on your own and admin a simple file server, serving data is very easy, stable, and cheap.
Amazon's options are prone to serious failure if you do something wrong with them. I don't lose my hard drive's contents when I accidentally pull the plug, but that is the case with EC2.