The NY Times today published this map:
What it represents is the shift between 2004 and 2008. Blue indicates a strong shift towards Democrats while Red (if there was any on the map) would indicate a strong shift towards the Republicans. White means the results were the same as in 2004. I guess this map pretty much tells the whole story. Other than a couple of states, the Democrats did better in every state, even the ones that they did not win.