Day two of leaving WiFi turned *on* all day long has yielded very surprising results: battery life is hugely improved.

At both my home and office, I have WiFi but very bad or nonexistent 3G signal. In a couple of days of using the phone with only 3G, my battery was hardly able to make it to mid afternoon.

With WiFi enabled, I'm at 80% at 5 pm.

Even though this seems completely counter intuitive to me, it's definitely working out well.