I have stayed at the Oriental some ten or so times and I love it. There is a special feel about this place that is hard to find elsewhere. And yet on my most recent stay (October 2008) I had the feeling that something was changing about the hotel. Somehow the level of service was not quite what it had been in the past, the food was not quite as good and there was a "je ne sais quoi" about the whole experience which worried me. I later heard from a Thai friend who is a stockholder in the hotel that it is (or has?) changing its name from the Oriental to the Mandarin-Oriental. She feels, and I agree, that this would be a big mistake. So is this part of what I felt?
We left the hotel this time with an impression that it is getting very over-priced for what it offers. Our room rate included the buffet breakfast on the terrace. This was fantastic in the past but they have re-worked the kitchen and there seemed to be far less on offer than before. Their dinner cruise on the river, for example,costs around $70 per person. The evening was nice and the food OK but not wonderful, and there was very little information offered on what we were seeing. The following week we joined a group of friends on another dinner boat, at $35 or so per person, and the food on that boat (Loy Nava) was really terrific, the "tour" information on the sights we were passing fantastic and as a result we had a great evening.
Perhaps all this is a passing phase and things will come back to normal at the Oriental but if they don't I wouldn't want to spend all that money ($550/night or so) to stay there again. That would be sad.