I realize one more thing, when I try to browse at a very weak 3G/Wifi signal location, my batteries drain very fast. Not to mention the page took more time than usual to appear.

When I tried the same at a better signal location, the batteries last longer and this make me wonder if signal strength actually contributes to battery's usage?

Anyway, I'm upgrading to 3.1.2 and hopefully I can save some money from getting a car charger.