While InfoPath 2007 does not offer support for printing web-based forms to PDF, you can host your form template in a custom ASP.NET page, and use the NotifyHost method of the XmlForm class and the NotifyHost event of the XmlFormView control to implement a solution that will allow you to print your web-based form to PDF.

The technique described in this article is not limited to printing web-based forms to PDF. You can use it to print forms to any file format, provided you write the appropriate code to convert the XML of a form to the file format you desire.