Active Directory/Documentation/IE7 Feeds
The RSS store is a set of OLE documents (a two-decade old technology, which is not cross-platform), and is installed on a per account basis. If your Windows account name is <user>, then the RSS store is stored in:
C:\Documents and Settings\<user>\Local Settings\Application Data\Microsoft\Feeds\FeedsStore.feedsdb-ms
We could write a script to add RSS feeds. More info here: http://www.arstdesign.com/articles/rssstoreviewer.html
Or, we could change the install image so that newly installed computers have default feeds.