Another tool that could help with your schema changes is SQL Compare Pro 6.0 by Red Gate (disclosure #1: I do work for Red Gate; disclosure #2: I'm the architect of the tool in question). It allows you to read in SQL files and compare them directly with another set of SQL files or with a live database. The nice thing is that it allows you to synchronize the changes in both of the directions, so you can update your live database as well as your script files to reflect the changes. Upgrading the scripts directly clearly has some limitations, I summarized these on Source Control and Databases. On the other hand, with this tool you can support both of the common development styles (and their mixtures), i.e. one where you maintain a set of creation scripts and execute them to get a db, and one in which you change the db directly, but want to update your SQL scripts in your source control.

Andras