And "Trend" is exactly what you are talking about with your second question. Swing is simply the change in each state from one election to the next, while Trend is the difference between the national swing and the state swing (thus there will always be a roughly even split in the states that trend each way in each election).
Oh, sorry, I think my wording was off. What I really meant was, a red vs. blue map that shows the percentage of the vote in each state relative to the national average. Not the year-to-year swing relative to the national average. So, for example, in 2004, you'd have Iowa, New Mexico and Ohio for Kerry because he did better there than he did in the national popular vote. But everything else would be the same. Just so you can see "these are the states that were more Democratic or more Republican than average" even in landslide years. You already get that a little in the different shadings of the maps in the Atlas, but it's not convenient for comparing different years and so forth.
