I would say if you plan to use it for an entire day, you will need a charging source (laptop, wall outlet, etc) near by.
This is after 0.5 a day of use. (Had WiFi on, Browsing for most of the time, trying to get use to the keyboard).
I have a charger everywhere I go, and charge it at least twice a day. I do use it a lot more than I used my bold 9700 because of the browser, and all the apps.