Utter nonsense. iCloud has nothing to do with killing Windows, but is simply a recognition of where things are headed.
For the longest time we all had the need for sizable storage & horsepower on our desks... eventually we became comfortable having it in a form factor we could fold and carry with us (laptops), while at the same time others got used to being able to do sizable amounts of their data generation & consumption from even more limited & portable devices (phones & tablets).
iCloud is simply a way to make the migration to even more portable devices easier.
It is interesting though that Robert ignores Microsoft's foray into the cloud syncing market... Live Mesh (now Windows Live Mesh 2011)... and if we ever put some marketing behind it (and either tied it better to SkyDrive, or had it support WP7), it would have a better potential user base than iCloud ever could.