Agreed with TorontoColin. For what you are getting, the price is a little steep; especially considering the limited app selection right now. Even the Office RT package is just a preview, and it hasn't been revealed how much that will actually cost to unlock it.
Even the overall specs seem a bit underwhelming for the $499 price point when you factor that something like the ASUS Transformer Pad Infinity costs the same, yet has a 1080p screen and probably a faster processor. The keyboard dock for the Transformer is slightly more than the Surface's keyboard covers, but also has the benefit of housing a secondary battery. Spec-wise, this is more competing with the $399 Android tablets like the Transformer Pad TF300 or even the recently-announced $439 Lenovo IdeaTab S2110.
Right now, it's the "Windows" name that has the potential to help sales of the device; but as hugh indicates, there is a very possible risk that buyers will think they can run their standard apps on Surface RT.
Overall, with this price (and the cost of the additional keyboard covers), Surface RT just doesn't have the appeal that it did when Microsoft first showed off the device.