For development reference, `drush si totem` (beta3) successful installation with minor warning:

drush si --db-url=mysql://XXX:AAA@localhost/d7_totembeta3 totem
You are about to create a sites/default/files directory and create a sites/default/settings.php file and DROP all tables in your 'd7_totembeta3' database. Do you want to continue? (y/n): y
No tables to drop.                                                                                           [ok]
Starting Drupal installation. This takes a few seconds ...                                                   [ok]
WD php: Warning: mb_strlen() expects parameter 1 to be string, array given in drupal_strlen() (line 478 of   [warning]
/totem-7.x-1.0-beta3/includes/unicode.inc).
Installation complete.  User name: admin  User password: TuvY5QX4WH                                          [ok]
mb_strlen() expects parameter 1 to be string, array given in drupal_strlen() (line 478 of                    [warning]
/totem-7.x-1.0-beta3/includes/unicode.inc).
Content permissions have been rebuilt.                                                                       [status]
Site-Install installed successfully!                                                                         [status]
To integrate Site-Install with Facebook you will need to enable the Facebook OAuth module, then set the App  [status]
ID and App Secret created for your domain. See the Totem User README for further details.

It doesn't seem to cause a major downside, but still worth noting.