I’ve been experiencing crashing events with both Revit 2009 and 2010. I finally narrowed it down to Internet Explorer 8. The funny thing is that these problems started with the released version of IE8 and not the Beta! This was filed this with Autodesk Support and turns out to be a known issue. Their response perfectly describes the symptoms I was experiencing. You have now been served!
“Thank you for choosing Autodesk Support.
Internet Explorer 8 is not recommended to be installed when used with Revit 2009 64 bit. There is a known issue with the recent files screen. The Recent Files menu is an HTML based window and uses Internet Explorer and has not been designed to be used with IE8.
IE8 is also not recommended to be used with Revit 2010 as it has not been designed or tested with it. The same problem does not exist with the recent files screen in the same way but it is apparent that if you have the recent files window up and TAB+CTRL between your windows while using 64 bit and IE8, it will crash. You can use IE8 if you do not have the recent files window open.”