When you see
all 3 readers next to each other, it's pretty clear that the Daily doesn't have a 7"
diagonal screen. I think when they 7" wide, they actually mean 7" wide when put in landscape mode.
EDIT: Some quick back of the envelope calculations with Photoshop show that the diagonal on the Daily's screen is about 7.7". That's assuming that the side-by-side shots are fairly accurate representations.