Haven't we been here before. In 1996 or so both sun and oracle were hyping network pc's. That's seems to be no different than now except we have re-branded this client/server architecture "cloud computing".
I seem to recall a video where (i think ellison) was describing how your desktop would follow you no matter what pc you were sitting in front of. That is the same theme that Google had yesterday during there presentation.
As a sw engineer at one of the worlds largest aerospace and defense contractors we don't store much locally on our pc's. Our source is in SCM systems, the same with bug tracking and change requests. Most of our documents are on SANS to improve collaboration and sharing. So I guess i'm just not seeing something "entirely new" here.