The PHPBase project has been released and is in the alpha stages currently.
The main purpose for a tool like this is the need to keep data submissions accurate and avoid common errors that might occur when submitting to standard schemes recommended by Google.
The code still in development, and will be added to a subversion repository once we get the project approved at berlios.de.
PhpBase is a set of Open Source PHP classes and functions aimed to help developers submitting their data to Google Base.
You can check out the main site here or just download the current version directly...