The charts below show the relative strength of Value vs Growth stocks as measured by Morningstar's various ETFs (rising line indicates outperformance of value versus growth stocks). Since July 2004, small cap value has only slightly outperformed growth, and mid cap value has actually underperformed growth. The only area where we have seen a wide disparity between the performance of value over growth has been in the large cap area. (In order to show the differences in performance, we have kept the scales for all three charts the same).
After thinking about this, it does make some sense. Large cap growth stocks were the darlings of the the last bull market which resulted in extremely high valuations for the group. Since then the group has been "sleeping off the party of the nineties."