The long awaited Analysis Services 2005 Performance Tuning guide is now available at
http://download.microsoft.com/download/8/5/e/85eea4fa-b3bb-4426-97d0-7f7151b2011c/SSAS2005PerfGuide.doc
I know that it has been a long time in the making but hopefully it is worth the wait.
Enjoy!
Liz