I don't manage deltas. I make changes to a master database and have a tool that creates an XML based build script based on the master database.
When it comes time to upgrade an existing database I have a program that uses the XML based build script to create a new database and the bare tables. I then copy the data over from the old database using INSERT INTO x SELECT FROM y and then apply all indexes, constraints and triggers.
New tables, new columns, deleted columns all get handled automatically and with a few little tricks to adjust the copy routine I can handle column renames, column type changes and other basic refactorings.
I wouldn't recommend this solution on a database with a huge amount of data but I regularly update a database that is over 1GB with 400 tables.
