Finally.  Yesterday we republished the TFS 2010 SP1 Cumulative update.  You'll find the download here:

You can read my original article about it to learn more:

To refresh your memory, the update was pulled due to two bugs:

1) Installing it on a TFS Proxy server broke the proxy server, requiring uninstall.

2) After installing it on a TFS server, subsequent imports of TFS 2008 servers into TFS 2010 project collections was broken.

Both issues have now been fixed and verified and the update republished.  There will be a new KB article published but, like last time, I expect there will be a noticeable lag between the download going live and the KB being published.  For now the download points at the original KB article which is accurate except for the two fixes I listed above.