The update process comes in two packages, with a 26MB package to prepare the phone (it's a big jump from Gingerbread to ICS), then a second 390MB OTA complete with ICS and LG's touch from the Optimus UI. When things are done, you're running firmware version VS920ZV7 and Android 4.0.4.
Since it's a big change, Verizon and LG have dropped a few hints in the OS, specifically about the app drawer layout and finding widgets with the new system. Our tipster tells us "The update is pretty nice so far", and he may just start carrying this device again. Those are the kind of update stories we like to hear! Hit the break to see what we're talking about here.
If you haven't been already, start hammering the check for updates item in settings, then hash it all out in the forums!