Django multi-db: Route all writes to multiple databases
I was looking for something similar. What I found is: 
1) Try something like Xeround cloud DB - it's built on MySQL and is compatible but doesn't support savepoints. You have to disable this in (a custom) DB engine. The good thing is that they replicate at the DB level and provide automatic scalability and failover. Your app works as if there's a single DB. They are having some connectivity issues at the moment though which are blocking my migration.
2) django-synchro package - looks promissing for replications at the app layer but I have some concerns about it. It doesn't work on objects.update() which I use a lot in my code.
I am currently sitting in front of a more specific problem which has to do with fail-over support / redundancy for a specific web site which will be hosted over @ WebFaction. Unfortunately replication at the DB level is not an option as I would have to install my own local PostgreSQL instances for every account and I am worried about performance amongst other things. So I am thinking about using Django's multi-db feature and routing all writes to all (shared) databases and the balance the reads to the nearest db.
My problem is now that all docs I read seem to indicate that this would most likely not be possible. To be more precise what I would need:

route all writes to a specific set of dbs (same type, version, ...)
if one write fails, all the others will be rolled back (transactions)
route all reads to the nearest db (could be statically configured)

Is this currently possible with Django's multi-db support?
Thanks a lot in advance for any help/hints...