As your SharePoint deployment increases in content, number of sites and in hierarchical complexity you may want to consider a tool for managing metadata. A recent blog post discusses three different tools that could help. Go check it out. In a different post, the same author also talks about migrating content into SharePoint while maintaining metadata.
Metadata management is becoming one of the FAQs that customers are asking. A couple other posts worth browsing are:
We generally have a pretty in-depth conversation on metadata management, the role of content types, and the necessity for planning. Grab a cup of coffee and dig in prior to deploying SharePoint. If you've already deployed, it's not too late but you might need 2 cups of coffee...