Battery life not like advertised on new MacBook Pro

Question

I bought a MacBook Pro 15.4" in September and the battery life is nothing like what is advertised. I'm struggling to get 4 hours out of it with wifi off and Ethernet as my network connection. The spec I choose wasn't the best, either: it only has the 2.2GHz Core i7 with the better graphics card model, no other additions.

I bought it because of its great battery life, I've tried turning screen brightness down and the keyboard backlight off and still nothing. I am mainly using it to type up lecture notes in the lecture so I am running it off battery power only using Word and PowerPoint. Should I be concerned and take it back to Apple? I know the Core i7 is power hungary but, still, this is ridiculous as it's less than a month old – I was expecting to be able to use it for a full day without the battery dying.