I have to say that I find the ability to resync my Kindle invaluable. Most of the stuff I want to do in the cloud is light-weight consumer stuff and not enterprise grade work.

Storing basic stuff in the cloud is useful provided I don't want to store private data and the latency and availability are of mintor concern.

One thing that does worry me about the cloud is data destruction. How can I be sure that data I want destroyed is destroyed?