No, it's not fixed yet, but here's a bit more information:

The Windows Home Server team has been heads down working on the data corruption issue since we first posted the Knowledge Base (KB) article in late December 2007. An update to the KB article was posted today that provides more information regarding symptoms, cause, status and guidance.  You can read the KB at http://support.microsoft.com/kb/946676.
 
One question that is getting asked is, “Will I be affected”? We are aware of only a very small percentage of users with confirmed instances of this issue, and we believe that most people are unlikely to be affected.  In the KB article we offer up some precautionary measures that people can take. Some of the instances that were initially attributed to this issue ended up being something else, such as a faulty network card/driver, old routers with outdated firmware, or people incorrectly testing the limits of their home servers. 
 
From the outside looking in, some people would say “Why is this taking so long?” Fixing this issue is the Windows Home Server team’s top priority and the team is making good progress on the fix. We understand the issue really well at this point - it is at an extremely low level of the operating system and it requires thorough testing to ensure that the fix addresses the issue. We have coded a part of the fix which is currently being tested internally.  Internal testing is expected to continue for at least several more weeks. 
 
Once the patch has passed internal quality bars, external participants will be asked to help test the fix. Our current plan is to release beta test versions of a fix over the next few months, with a final version currently estimated for June 2008, although that date could change as testing progresses. Thorough testing of the fix is critical and will take time. 
 
If you believe you have evidence that you are experiencing the issue, please send a detailed email of your circumstances to whsforum@microsoft.com, so we can attempt to validate the cause and provide specific guidance.   Thanks for your continued support.
 
The Windows Home Server team

In a separate note I received, Microsoft has more specific information about what you can do to avoid the data corruption issue:

  • Employ Windows Explorer or a command line tool to copy files to and from the Windows Home Server.

  • Do not use applications to directly edit or change files stored on Windows Home Server.

  • Do not use media management programs, such as Windows Media Player, to import files to the Windows Home Server.

  • Do not redirect applications to access files stored in the shared folders, as some applications may make changes to the metadata of a file without explicit user action.