Ask HN: Best Practices For MongoDB with Amazon EC2+EBS?

So I am a happy MongoDB user -- with a web app that is about to go public (which means I can't predict the actual load yet and my application would have to change fast and soon). I have been doing my back up etc. Although reading all these scary MongoDB related articles have not had much impact on my architecture , I do wonder what could I be doing to prevent things from going wrong. (I can't afford paid support just yet)

Is there a set of MongoDB best practices for EC2+ EBS ? For the setup configuration and deployment architecture ? Best patterns for usage of API ? Are there any MongoDB recommended AMIs I should be using ?

I want to reiterate that I have faith in MongoDB and my application architecture.I find MongoDB to be well documented and well supported. I am merely seeking all this information in one place.