We are in the process of migrating the web services we have running on windows in the Amazon cloud over to new servers based on Ubuntu Linux. There shouldn't be any interruption to service as the new servers will silently take over from the old as the dns changes propagate around the web.
Do let us know if you experience any problems though ...
Following feedback from our users, we have changed the XML format of the backup files with immediate effect. More information on our support forums
Just a quick update to say that we're investigating a problem where some users are receiving "The specified domain does not exist" errors when trying to access their data. This seems peculiar to only some accounts and we're looking into the cause in more detail.
UPDATE: Have located the bug, the fix will take an hour or two to test and deploy.
RESOLVED: Fix deployed and tested 
XML Feeds