Converting Custom Taxonomies?

So I’ve got a lot of information in tags and custom taxonomies. I need to change it to be specific to certain custom post types (I just switched to 3.0)

Basically, I have a huge amount of posts that are currently set with tags that I need changed to the custom taxonomy I’m not setting .

I ALSO have another set of info in a custom taxonomy that needs to be changed to a different custom taxonomy slug that is specifically applied to the one post type.

Is there any way to do this besides manually doing it on every post? I’ve got thousands!