The idea of the cloud really works for me, but I've stumbled over a simple technical issue: timezones. I added a meeting to my calender while I was in CST, but the meeting is in the UK and I used the UK time on my Android device which is set to switch automatically to the local timezone. Net effect: the meeting ended up in my diary an hour early.
Looking at Google Calendar on the web I can select the timezone for my booking, which is neat, but the Android app doesn't offer that facility as far as I can see. Not an unreasonable simplification for a mobile interface, but still a potential source of error.
It so happened I realised well ahead of time, but it's an interesting example of how physical travel and its vagaries can impact the homogeneity of the cloud. After all I have no idea and seriously don't care where the server that stores my Calendar data. But somewhere along the wires something does need to know.