Database prefixes in settings.php

I have been messing with MySQL views - see http://drupal.org/node/291373

This approach is all well and good, but because Drupal is not aware the viewed tables are in a different database entirely, updates must be handled with extreme care. Now here's my idea:

It would _awesome_ if you could take the whole table prefixes model one further. At the moment, in settings.php, I can do something like this:

   $db_prefix = array(
     'default'   => 'main_',
     'users'     => 'shared_',
     'sessions'  => 'shared_',
     'role'      => 'shared_',
     'authmap'   => 'shared_',
     'sequences' => 'shared_',
   );

This is great, but _this_ would rock my world!!

   $db_tables = array(
     'default'   => array(
            'server' => 'mysql4',
            'database' => 'site1',
            'prefix' => '',
             ),
     'users'     => array(
            'server' => 'mysql1',
            'database' => 'shared_database',
            'prefix' => 'shared_',
             ),
     'sessions'  => array(
            'server' => 'mysql1',
            'database' => 'shared_database',
            'prefix' => 'shared_',
             ),
     'role'      => array(
            'server' => 'mysql1',
            'database' => 'shared_database',
            'prefix' => 'shared_',
             ),
     'authmap'   => array(
            'server' => 'mysql1',
            'database' => 'shared_database',
            'prefix' => 'shared_',
          ),
     'sequences' => array(
            'server' => 'mysql1',
            'database' => 'shared_database',
            'prefix' => 'shared_',
          ),
   );

I can define a database server, database name and table prefix (if required). This way I can distribute my content across multiple machines and Drupal can still manage updates safely, which would be brilliant and (combined with some of the excellent work going on in caching) would be a large step towards sealing Drupal as an enterprise-level CMS. =)