I just wanted to note that the Presentation about "Upgrading Joomla! 1.0 with VirtueMart to Joomla! 1.5" has been updated recently, right after I discovered mtwMigrator. This is a Joomla! 1.5 component, which can directly retrieve all the entries from your "old" Joomla! 1.0 database (including all VirtueMart Tables!) - so it's the other way 'round compared to Sam Moffatt's Migrator (where you have to create a database dump and upload it during the J! 1.5 installation).mtwMigrator makes migration easier, because VirtueMart Tables don't have to be converted by hand now anymore.
Make sure to check out the updated presentation: Migrating from
Joomla! 1.0 to Joomla! 1.5.