I have just installed dawnguard and 1.6 patch.
Now when obtaining the shout which is at Arcwind point, Arngeir (the guy who tells you where to find the shouts in High Hrothgar) will now only tell me to go to Arcwind point.
The quest marker lays on the floor in front of the wall whether i have obtained it via his instructions or if i obtain it before asking him if he knows where any are.
Therefore i can't ask him for any more shout locations as the dialog option will not appear (the quest to get the Arcwind Shout remains active even though i have found it already).