400 for 16gb, 2560x1600 resolution on a 10" screen, the new exynos 5 dual-core processor that takes a crap on tegra 3 quad-core and an amazing gpu to boot.
however, this is still a good deal. for $300 you get a very capable tablet with an sd slot, the nexus 10 does not come with one...but personally, im waiting for nexus 10 review. i can do without an sd slot.
Actually, early benchmarking shows the Exynos 5 dual core to be of slightly lower performance than the tegra 3. It is a tad more energy efficient which will help battery life, though. Even Samsung admits and supports this. The nexus 10 will be the best $400 tablet out on the market as it will still handle all tasks admirably yet with an awesome 2560x1600 res. screen.