The Asus Vivo Tab RT, formerly known as the Tablet 600, is now available for pre-order for $599.99 online.
The price only includes the Tablet part though. The keyboard/dock will be available for an extra $200.
TigerDirect has a bundle with both the tablet and keyboard for $799.99
The Vivo Tab RT has 2GB of memory, a Tegra 3 processor, 10.1-inch 1280 x 800 IPS display and 32GB of solid state storage
Once again, you can find this at TigerDirect.