Update: T-Mobile says that much of the data may indeed be recoverable on Microsoft's backend, according to the New York Times. Engineers in Redmond are "optimistic that much of it can be recovered," but individual customers have yet to be notified whether their data is part of that pool
Earlier this week, T-Mobile Sidekick owners figured out that if they let their battery die, their phone would block out all access to their contacts, calendars, to-do lists, and photos. Needless to say, they were pissed.
At first the locus of rage was T-Mobile, but savvy Sidekickers soon figured out that Microsoft was to blame. (Redmond bought the Sidekick data provider, Danger, in February 2008.) How exactly did they figure it out? T-Mobile sent them all a letter placing the blame on its partner, which apparently botched a server upgrade without backing up customer data.
"Regrettably, based on Microsoft/Danger's latest recovery assessment of their systems, we must now inform you that personal information stored on your device—such as contacts, calendar entries, to-do lists or photos—that is no longer on your Sidekick almost certainly has been lost as a result of a server failure at Microsoft/Danger," the T-Mobile letter read. Lest you forget, Microsoft has also been crapping the bed with its own branded mobile disaster, Windows Mobile 6.5.
The trend #microsoftsucks began to supplant the earlier #tmobilesucks almost immediately on Twitter. For a good survey of the rage, check out BusinessInsider's tweet summary here.