but I looked at the map of Skyrim, the one that will also be included with the game, and I noticed there are "X" marks all over the map. I didn't give it much thought first but yesterday I counted them and as far as I could tell there are 16 such "x" marks on the map. Coincidence? 16 marks, 16 daedric shrines?
http://www.citizengame.co.uk/wp-content/uploads/2011/10/skyrim-map.jpg
As I said, I am just guessing. But maybe someone who already found a shrine or two could confirm they were in a spot where there are also marks on the map.
One example of such an "x" mark is right of Whiterun below "White River" on the map.

. But coming Friday I will for sure check out one of these spots to see what can be found there if nobody confirms before who has already had the chance to explore Skyrim.