Norton Internet Security 2009 and Norton AntiVirus 2009, incorporating numerous performance improvements, are now available as public betas
.Norton 2009 is supposedly less demanding of computer resources, in terms of both footprint and performance. According to Tom Powledge, Symantec's vice president of consumer product management, while Norton Internet Security 2006 consumed roughly 300MB of hard-disk space, the 2009 version is coming in around 100MB. Performance has been improved by scanning only files that have changed since the last scan, so that digital photos, music, and other media files--space-hogging files that don't typically change often--get marked as "trusted" and ignored on subsequent scans.
Also, in order to keep up with the flood of new malware, the 2009 products will be updated with new malware signatures several times an hour.PC World