Dramatically short battery life of LG Nexus 4.

I've been using the new LG Nexus 4 for about 10 days now after switching from the iPhone 4. Overall I'm very satisfied with the quality of the hardware as well as Android 4.2. Everything is smooth and as compared to iOS, the capabilities of this device are limitless.

Yet there's one thing that really irritates me and it's the battery life. I'm not sure if it's the device or the system or maybe some 3rd party apps. I continuously try to kill apps which I don't need (which is very annoying), I turned off 3G/HSPA and overall I don't use the phone all that much and still can barely make it till the end of the day.

Today for example the phone has been on for 7 hours now, screen has been on for 1.5 hrs total, EDGE/WiFi connection for the most of the time and I have less than 50% battery left. The major culprit is "Android OS" process (not sure what that means, there's also "Android System") which consumed over 30% of the battery.

I think it's very disappointing that such a great device is totally crippled by its battery. I don't have a chance to plug it in during the day so if I go out after work it pretty much dies on me after 12 hours of light use. Where light use is browsing the web for 30 minutes, sending a few texts and emails and watching a 10 minute video.

Is there anything I can do or just turn off pretty much everything and dim the screen? I'm totally new to Android and really like it after 10 days of playing with it. I don't want to go back to iOS but my old iPhone 4 lasts much longer with 3G and full brightness on. Please help!