I don't think it's possible for a framework like Django to support sharding out of the box - there are just too many different ways you might want to implement it. Digg shard by date for example, whereas a site like Flickr shards by user. It completely depends on your application. The database router stuff feels to me like the furthest a framework can go - though maybe a bunch of common routing patterns will emerge in the future.

I can't find a reference to it, but I recall one of the developers mentioning that the current multi-db support lays the ground work necessary for sharding.

I would bet that once 1.2 is released at least several reusable apps pop up that implement various sharding/partitioning strategies.

From personal experience, South is not ready.

I end up spending 10x the effort using it than writing a few custom queries to add columns or drop a table.

I'm sorry about that. We get a lot of spam comments so I was constantly checking the Wordpress page to approve comments. For some reason a HUGE chunk of them didn't show up until just now. I approved all comments that weren't spam. The ones that were there when your comment wasn't there were people who had commented before and were auto-approved. Again, I'm sorry you felt that way, it was not the intention.