I can only report on what I've seen and heard. Here in Toronto Surface was sold out for a month straight. Only in the last week or so are you able to find it consistently in the 2 Microsoft stores without calling ahead and checking for stock.
Early this week Microsoft Stores in Toronto reduced the price of Vivotab RT (the other RT tablet) from 599 to 399 and are throwing a free keyboard as well. Pic from the MS store sale in Toronto below.
I asked them why last night and they said that no one is buying them, everyone wants the Surface...so they have to clear stock. So I don't buy this whole, Surface isn't selling. Check ebay prices and at what cost they are selling when auction is over and you will see that they still sell at cost if not over cost.
Issue is distribution, not demand.