I think you'll find 7.1 will be replaced with 7.5
"GRISOFT is announcing a new version of the AVG Anti-Virus Free Edition. This new 7.5 version with improved performance and full compatibility with the latest Windows Vista version is available. Users that are using AVG Free 7.1 will be provided with a specific dialog, within the next few weeks, with the opportunity to choose the right option fulfilling their needs. AVG Free 7.1 version will be discontinued on 15th of Jan 2007."