What is a consideration when setting up the beta version of the State and Country Picklists feature?

State and country picklists are available on certain standard objects.
Planning and feature enablement require working with salesforce.com
Validation rules must be created to enforce data entry standards.
Reports, email templates, and list views are automatically updated.

Read this – http://help.salesforce.com/apex/HTViewHelpDoc?id=admin_state_country_picklists_overview.htm&language=en_US