Here's a roundup of the current state of the Microsoft/T-Mobile SideKick user data loss fiasco...

Here's a couple of things T-Mobile has done on their side...

CNET: T-Mobile halts sales of Sidekick

Gizmodo: T-Mobile Lets Furious Sidekick Users Ditch Their Contracts for Free

T-Mobile Forums Sidekick Data Disruption thread: In the event certain customers have experienced a significant and permanent loss of personal content, T-Mobile will be sending these customers a $100 customer appreciation card. This will be in addition to the free month of data service that already went to Sidekick data customers.

Then, there appears to be a bit of good news for some Sidekick users...

InfoWorld: Some Sidekick users report data has been restored

And, if you have the third party Intellisync for Sidekick app installed, here's T-Mobile's documentation for using it to sync Sidekick data (contacts, calendar) with Microsoft Outlook...

T-Mobile Support document: Intellisync for the Sidekick

Good luck and best wishes to T-Mobile Sidekick owners. Let's hope this disaster serves as a wake-up call to service providers and customers alike to help prevent another incident like this one.