Developing for the cloud, thinking about MongoDB?
If not, maybe you should be. Or at least you should watch this talk by Eytan Daniyalzade, software developer at chartbeat.com, who chronicles almost two years of experience running MongoDB on EC2.
To be honest, the combo doesn't sound like a flawless victory to me. For one thing, MongoDB's global read/write lock sounds less than perfect for EBS.
But don't take my guess for it: recall foursquare.com's 11-hour outage last year, which in part cascaded from some imperfectly-tuned interactions of MongoDB and EC2 (performance-related, unsurprisingly). (See this fuller discussion for details on the outage, particularly re. sharding, or watch foursquare's own MongoDB presentation from this May.)
10gen gave a webinar introducing MongoDB on AWS earlier this year -- pretty long and fairly technical, but a good manual-style treatment. Watch if you want to hear the creators' story.But it's always good to pair a manual with a user experience, especially a less dramatic experience than foursquare's. So check out Eytan's presentation too, which is full of pluses and minuses but overall communicates a very positive MongoDB + EC2 experience.