The latest release of PythonCard contains XML-RPC and SOAP samples and the radioclient sample app for Radio Userland 8 and other Blogger API services. This release also contains a much improved layout editor (resourceEditor sample) for building the GUI layout and menus for your app.
The documentation page has links to installation instructions for Windows that covers installing Python, wxPython, and PythonCard. Dan Shafer wrote some introductory walk-throughs to help new users get started writing their first application with PythonCard. Check the changelog for a complete list of changes.