Although it's not as popular as Views, the Panels module has a reported usage of more than 100,000 installs! Not too shabby. If you haven't tried Panels yet, it's a little hard to wrap your head around it at first when you are used to Drupal's built-in block configuration. But, if you are willing to take the plunge, you'll find that Panels is an awesome tool for sites with non-standard or multiple layout requirements. David Mercer's Drupal 7 book has an introduction to Panels, but, for more in-depth coverage, Bhavin (Vin) Patel has a Drupal Panels book and Earl and Lynette Miles wrote one for Panels, CCK, and Views. I'll assume you know how to use Panels for this section.
The language behavior of panel panes depends on the pane content. For example, if you add a multilingual block, then you will see the language-specific block content when viewing the panel with another language. This is the same for any component added to a pane including nodes, menus, variables, and forms...