Build three is out. Download it here. Here is what it does straight from Autodesk's web page.
Improvements made in the Web Update #3 build (20071109_2345):
Consistent Electrical Fixture insertion behavior after creating Electrical Fixture schedules.
Improves performance when placing Callouts on MEP models in certain situations.
Allows the ability to array face-based families placed on a vertical face.
Allows the ability to maintain face-based instances on curved surfaces of a Revit link when the link is unloaded.
Improves stability when selecting Sections.
Allows the ability to insert an electrical receptacle into a legend view.
Improves stability when accessing the Help menu in Revit MEP on a computer with the Microsoft Windows Vista operating system.
Improves stability when applying a view template to a sheet.
Improves performance when views contain many objects with overridden graphics by element.