You would be amazed how the settings on your TV will make or break your BF3 enjoyment. I own a Bravio 2500 circa 2007 that actually made my eyes dry out. I was dismayed and went to a eye doc .. my vision had actually increased over the past year. Hah! Anyway, in 2009 I had added a blog post on my site with reference pictures I stored at microsoft.com.
I went thru the process and woah! Things change in LCD's .. primarily the amount of light they emit. As a Sony Bravia Poor Man series owner I had already done the AVSforum remedies. I copied this years ago and it actually worked. http://www.memphispcguy.com/gaming/calibrate-xbox-360-hdmi-settings
Your MSLive account should allow you to DL all the reference pics but if not , read and download the 5 you need. Its a poor mans calibrations but you will be amazed how much happier you are just because you stopped guessing and started seeing
Google Search Xbox 360 Calibrate HDMI for direct links. Memphis PC Guy is the URL.