Now that is progress by Oracle. Oracle SQL Developer incorporates migration support by including redeveloped features and greatly extending the functionality and usability offered by the original Oracle Migration Workbench to migrate Microsoft Access, Microsoft SQL Server, MySQL and Sybase databases to Oracle.
I started using Oracle SQL Developer a few months ago and find it quite easy to use. Not sure whether the migration functionalty was there at that time or did they just introduce it into the package. For those who are interested, you can download a copy here or just wait for Oracle Database 11gR2 in which it will be included.
* For those who want to migrate PostgreSQL to Oracle, you might be out of luck since it’s currently not supported.