"when will sys.dm_exec_query_stats be fixed to report worker time (cpu) for queries with parallel execution plans?"
The answer to this is that we have already fixed it, but the code has been checked into the next version of SQL Server (i.e. the next major release after SQL 2008). When it was fixed we also fixed another problem where the same DMV can report NULL in the dbid and objectid columns under certain circumstances.
Currently there are no plans to backport this fix into SQL 2005 or 2008.