You have jumped squarely on the industry pundit bandwagon for this column. Online storage is much more expensive than local hard disk. Bandwidth is still insufficient, and will be a for a long time.
Security is questionable.
I cannot imagine restoring my 30 Gig of data over a 768kbs link. I cannot imagine restoring 5 Gig of data. Online archives are a good idea - but have not matured yet. They need to eveolve into active local apps that help users archive data files only to offsite storage. Video conferencing will catch on, but still needs generations of growth.