I would love to see a little Windows application (like the Mozy.com service) added to the Live CD that would help people migrate their data from Windows to Ubuntu. The application would connect to a Web-based service and would upload all data from the current machine to a secure offsite backup. The machine could then have Ubuntu installed and the data would be migrated back down from the secure site to the (now) Ubuntu machine.
This service would make it a lot easier for me to get people moved over if I could show them their data was "safe" before doing the OS switch.
We should all be doing offsite backups on a regular basis, so why not have this as a feature of Ubuntu that actually helps you move into Ubuntu? Data storage is cheap; so is bandwidth (ignoring the fact that I live in a rural community with a fair number of dial-up users). Of course there would be security concerns as well. Users should be able to choose which files they would like to upload to the service. Certainly digital photos would be a huge thing that a lot of people would want to save, but don't really need to be "secured."
It's very possible there is already a service that integrates well with both Windows and Ubuntu that could be highlighted as both a backup and migration service for the home computer and small business market?
Update: I don't expect Canonical to provide this service. I think it makes sense to investigate companies (like Mozy, or Amazon storage or Dropbox) who are already offering the service. Of course if Canonical is interested in getting into this kind of business by offering an Ubuntu-served, Web-based backup tool that'd be awesome too!