[wp-hackers] 2 domains, 2 sites, 1 WP install

[Ken (WraithKenny)]

As almost all the content, will be similar (translations), and all the
code (Core, Plugins, Themes) will be the same, a better route then
MultiSite probably exists.

You can use the requested domain as a switch
(http://codex.wordpress.org/Editing_wp-config.php#WordPress_address_.28URL.29
to protect for canonical redirection) to pull up the appropriate
version of content. It might be tricky, as the translation has to be
served with CPTs or Custom Meta Boxes, but it should be possible.
Using a single blog makes sense as the content isn't so much
different, just translated. If it's actually different content, use
MultiSite.

Would probably make a really popular plugin if it could be done.