How can I automatically position a block in Drupal 7 (via a script, Drush, etc.)?
Updated answer:

I just committed https://drupal.org/comment/7000524 to support the Drush block commands in Drupal 7.  I also added a shortcut mode, where arguments can be used in place of options in instances where doing so would be unambiguous.  When calling block-configure from a bash script, though, you should always use the options form; otherwise, your script would break if a specification became ambiguous (e.g. if someone added a block whose delta was named the same as some region).

So, from the commandline:

$ drush block-configure switch_user sidebar_second 10


From a bash script:

drush block-configure --module=devel --delta=switch_user --region=sidebar_second --weight=10


The later works just fine from the command line, of course; it's just more typing.