Proposed resolution (October, 2008):
Change 11.4.5.3 [class.copy.ctor] paragraph 8 as follows:
The implicitly-defined or explicitly-defaulted copy constructor for a non-union class X performs a memberwise copy of its subobjects...
Add a new paragraph following 11.4.5.3 [class.copy.ctor] paragraph 8:
The implicitly-defined or explicitly-defaulted copy constructor for a union X copies the object representation (6.8 [basic.types]) of X.
Change 11.4.5.3 [class.copy.ctor] paragraph 13 as follows:
Add a new paragraph following 11.4.5.3 [class.copy.ctor] paragraph 13:
The implicitly-defined or explicitly-defaulted copy assignment operator for a union X copies the object representation (6.8 [basic.types]) of X.