My own tree is a bit broken so I can't test right now but you could you please file a JIRA as the NPE is wrong in any case.
I think the injection system misinterprets the @New as belonging to the @Inject Instance and not to what the Instance is injecting. If I guard myself against the NPE:s I end up with a
org.jboss.weld.exceptions.DefinitionException: WELD-000816 Cannot determine constructor to use for javax.enterprise.inject.Instance<[class org.jboss.weld.tests.scope.up2.Foo]>
which is a @New @Instance implementation
Have to check with Pete how to handle it or what is the correct behaviour