• Paul Randal address the whole tempdb data file per processor core story here:

    A SQL Server DBA myth a day: (12/30) tempdb should always have one data file per processor core

    http://www.sqlskills.com/BLOGS/PAUL/post/A-SQL-Server-DBA-myth-a-day-(1230)-tempdb-should-always-have-one-data-file-per-processor-core.aspx