Aqua Data Studio 7 Includes an ER Modeler
The Entity-Relationship (ER) Modeler we’ve built into Aqua Data Studio 7 is as powerful as even the best standalone database diagramming tools. Use it to design a new database from scratch, understand and clean up a database nightmare in your office, or visually understand entity relationships in existing databases to write more effective SQL queries. Then share your diagram with the team through Aqua Data Studio’s integrated Subversion (SVN) and CVS source control clients.
I’ve really missed creating Entity Relationship diagrams when using MySQL as they are fantastic during planning and of course offer great documentation for all developers, particularly as your project (and database) grows.
This will start filling a huge hole and help to close the gap in comparison to other vendors database tools.
ADS is a comercial product so hopefully diagramming will be added to the free MySQL Administrator soon.