Varien just published Magento 1.3.0 this morning. After testing the TypoGento functionality we just adapted the router to the new version. Additionally we added a correct implementation of the ACT menu state of the TYPO3 HMENU for Magento categories. The current version can only be run with version 1.3.0 of Magento.
We tested it once in a development site and it seemed to work out perfectly. Still, we recommend to not upgrade on a live site directly - like Varien recommends to have an upgrade test before live upgrading Magento to 1.3.0. We’re trying to get some more feedback from upgraders within the next days. If you upgraded and everything works out great - please post us a message. If you should find errors, please drop us a line as well or post it to the bug tracker. Thanks a lot.
The extension can be found at http://www.magentocommerce.com/extension/693/typogento. Have fun using it.