This comes from LG. I'll paste it right here:
"CPU Dual-core 1GHz NVIDIA Tegra 2
OS Android 2.2 Froyo (2.3 Gingerbread upgradeable)
Display 4-inch 480x800 pixel (WVGA) capacitive touchscreen
Storage 8GB internal, MicroSD expandable
Video recording/playback 1080p Full HD (@24fps), 720p (@30fps)
Camera 8MP with autofocus and LED flash
Connectivity 3G, Wi-Fi (DLNA compatible), HDMI
Battery High-capacity 1500 mAh li-ion rechargeable
Dimensions 123.9x63.2x10.9mm, 139g
Others 7.1ch Virtual Surround Sound, Gesture UI, DLNA, LG SNS 2.0"
Google Nexus S for example is 10.88 mm thin and HTC Desire HD is 11.8 mm. So yes, Optimus 2X is really thin. For more info, please check out PhoneArena. I dunno know how many RAM the phone has, and LG hasn't confirmed that either. My hypotetical guess is 1GB RAM because it's a Tegra 2-phone, and every Tegra 2-phone so far has 1GB RAM. But maybe I'm wrong. We'll see soon... OS Android 2.2 Froyo (2.3 Gingerbread upgradeable)
Display 4-inch 480x800 pixel (WVGA) capacitive touchscreen
Storage 8GB internal, MicroSD expandable
Video recording/playback 1080p Full HD (@24fps), 720p (@30fps)
Camera 8MP with autofocus and LED flash
Connectivity 3G, Wi-Fi (DLNA compatible), HDMI
Battery High-capacity 1500 mAh li-ion rechargeable
Dimensions 123.9x63.2x10.9mm, 139g
Others 7.1ch Virtual Surround Sound, Gesture UI, DLNA, LG SNS 2.0"