I just finished updating the site to Drupal 6.3. The reason I didn't do this earlier, was that Brilliant Gallery was not available for 6.X. Now it finally was, so I updated.

All in all, everything went smooth. The theme needed a few tweaks here and there, but nothing big. There's probably a few things here and there that do not yet work perfectly, but I'll fix them as I find them.

Thanks for the Drupal community for the continuous development!