Both videos are freakin awesome considering that they are both smartphones. No one should be disaapointed by the results of either device. You can compare them till you blue in the face and many will by the way. . .
The Evo looks nice, it seems to have more saturation. The iPhone 4 is more how your eye would see it plus that second mic helps with recording too, it sounds more crisp and clean. Looks like ill be in line for an iPhone 4!