Here you can get the Update 1 for Revit. Seems like there are several enhancements and bug fixes included. Even the Revit API have been enhanced and improved.
Autodesk Revit Architecture 2010 Update 1
Autodesk Revit Structure 2010 Update 1
Autodesk Revit MEP 2010 Update 1
And here are documents describing what’s new: