I too was considering a stay here in June when I am in BKK. I e-mailed the hotel about Platinum amenities and no reply so I decided to call. If I book an Exec Floor room I was told that I would not be upgraded to a suite as the Exec room is the best "room" in the hotel already. When I enquired about a Suite upgrade, they told me that a "suite" is not a "room" they are not obligated to upgrade Plats; however, if I wanted to pay for an upgrade I would be more than welcome. I believe it was about $50 USD in addition to the $82 rate -- for $132, there are many better hotels in Bangkok. I think the I-C BKK, for $122 Advanced Purchase for a Club Room, with upgrade to Club Suite as Ambassador, is a better deal, IF looking for a suite upgrade.
Having said that I really don't know what I am going to do -- perhaps I will just give up and stay at the Oriental for 4 nights and not worry about a thing, except, perhaps, the credit card bill at the end of the month!!