Are there are database changes to 1.30 (additional columns and/or tables)? Additional Stored Procedures? If there are changes, are any scripts included to add the new columns etc? If not, is there a script to drop all tables, so they can be recreated with the 1.30 scripts?
If no code changes have been made to 1.20, can the new 1.30 files simply be uploaded to override the 1.20 versions?
What about the CSS, are there any new CSS classes at all? Would a 1.20 theme work with 1.30?
1. You can download a list of files that were changed here: http://nopcommerce.codeplex.com/Release/ProjectReleases.aspx 2. Database upgrade script can be found in \NopCommerceStore\Install\Scripts\1.30 folder (nopCommerce_upgrade.sql file)