Maybe someone from StackMod would chime in on their experience with Riak...
StackMob isn't using Riak at the moment. Still building out features that use it.
Can anybody share experiences on using StackMob?
Their platform is pretty sweet I'd say. I've been using StackMob for the last two months and am almost ready to submit my app to the App Store. With StackMob I was able to build my data model in a few minutes and they automatically created a secure REST API. Would have taken me a few weeks if I didn't use them.