Since this hasn't been posted. Here's the steps to Root your device.
1. Install the LG driver. You're on your own with this one. Get it from LG Drivers
2. Download and unRar the attached file to your desktop.
3. On your phone, make sure USB debugging and allow unknown sources is checked.
4. Plug the phone into your computer, and make sure that Windows see the device's adb connection correctly.
5. Open the folder you extracted in step 2, and right click on the RootOptimusG.bat file. Choose Run as Administrator (If you're having trouble, don't run as admin)
6. You'll see this firs type the letter y, then enter.
7. When you see "Press any key to continue..." press any key.
8. You'll see it say "Restore my data" Look at your phone, tap the button that says " Restore my data".
The phone will reboot twice, be rooted, and ready for fun. To exit the DOS routine just press another key.
Here's the .bat script. Thanks to fiddy619 for translating.