How much hill climbing do you do? Weight is typically more important to someone in San Francisco than in Tampa. Of course it also has an affect on accelerating and decelerating, but this is less profound, and it's also something a lot of riders do less of, vs climbing. Also, where the weight is can make a difference; my commuter bike has panniers, which means I can bring books and other heavy things with me, but they mount high on my cargo rack, and raise my center of gravity, which makes the bike tipsy.

My road bike is about 19 pounds and my cross bike/commuter is about 29 without the panniers, or maybe 40 pounds when it's loaded up. There's a profound difference, like night and day.