Re: "They're proprietary. There's a high level of lock-in."
Agreed ... When I can get the source, compile it, run it on my own trusted systems, develop on it and run my apps from it then I will consider moving them to the AWS if I don't want to worry about them running in the future, and have no concerns over the information stored in them.
I won't be happy using this system for anything enterprise until I can do all of that.