1) Templates! (site integration, too. But maybe afterwards)
and
2) Cross-Language Forums []/testimages/icons/smile.gif[/]
I want to be able to have a different language for each category. For example Cat1 is in English, Cat2 in German. For me it makes no sense to let the user define his language in his profile. The discussion in the forum is done in one fixed language anyway. Move the language selection out of the user-profile. Let's have it as an option for the admin, when he creates/changes a category.