FreedomPop offers the Freedom Liberty 7" Android Tablet with free talk and text over WiFi for $49.99 with free shipping. That's a $100 savings and the lowest total price we could find. It features a 7" 1024x600 touchscreen display, Cortex-A9 1.2GHz processor, 2-megapixel front-facing camera, 4GB storage, 802.11n wireless, microSD card slot, and Android OS. (Note that its unclear which Android version is installed. Also, the voice plan includes 500 text messages and 200 anytime voice minutes free the first month; it costs $4.99 per month after.)
It's not guaranteed for Christmas delivery.