I was late to a presentation today because I had to floppy mail last minute changes between machines... All they need now is to tell me how I share documents to a pc wirelessly.
Of course a crappy 3G connection can make this a bit of a joke too.
Shouldn't be a problem to get started over wifi & adsl - most major updates like music and photos would be over wifi & adsl as well - the rest of the traffic will be incremental.