[citation][nom]cookoy[/nom]Can anyone enlighten me about what are the roles of T-Mobile and Danger? Thanks.[/citation]
T-Mobile offers phone service for "their" Sidekick phone. This phone stores most of its information on servers hosted and maintained by Danger, the company T-Mobile contracted to perform said duties. T-Mobile provides access to the service with their network, but I believe Danger does all the physical hosting.
Therefore, this loss of data is entirely Danger's fault (who doesn't back up data before upgrading harddrives?). I'm sure any losses suffered by T-Mobile as a result of refunds, cancelled service plans, etc... will be recouped from Danger as per some service agreement. After all, if Danger is a wholly-owned subsidiary of Microsoft, Microsoft is also liable.