Amazon offers the Sharp Aquos 80" 120Hz 1080p WiFi LED-Backlit LCD Smart HD Television, model no. LC-80LE650U, for the in-cart price of $2,299.99 with free shipping. Plus, you'll receive about $46 in Amazon Rewards. (This will be added to your account as a promotional code up to 35 days after shipment.) Assuming you'll use the credit, that's the lowest total price we could find by $46 and the least expensive 80" 1080p LCD HDTV we've seen. It features a native resolution of 1920x1080 (1080p), 120Hz refresh rate, LED backlight, WiFi content streaming (Netflix, Youtube, Pandora, more), USB, and four HDMI inputs.
Update: As a reader found, Costco offers it for the same price. (Non-members pay an additional $130 fee)