Hope this is not an April Fools' Day joke. Microsoft tells its partners that SharePoint Designer will be available to everyone free of charge as a download starting on 1st of April 2009. They are giving it away for free to customers so they could derive more value from their investments in SharePoint products. Please note, they are not discontinuing it, the next version of SharePoint Designer is going to be released along with new release of SharePoint Server.
Thank you, Microsoft :)