I can, now, set it to dev=default manually but what this means is that libao-1.1.0 by default kills alsa default software mixing.
The only alternative is to have any attempt at playing surround always fail to play more than stereo on a default setup. The bug reports about _that_ prompted the change to the current behavior.
These days everybody seems to have regressed to using a soundserver again anyway
Part of the reason for that is that ALSA provides so precious little in the way of programmatic configuration discovery. So far as I can tell, each and every user gets to script/configure his own setup, and then also explicitly configure the applications what to do. Applications can't even tell if a default setup is in use. It's all plug-n-pray.
If that's not the case, I'd love to hear about it. I agree the current behavior sucks.
Monty