Heroku's value proposition though is that they are taking away the back end worries for their customers so they can just deploy apps and not have to worry about it all. If I have to still worry about redundancy outside of their system then their service suddenly becomes a lot less useful.
I think the blame stops at Heroku who either need to provide more redundancy for incidents like this or let their customers know that if this type of incident arises there is little that they can do.
