I had a Carte Blanche card for a while.. I booked one room through the travel service for a resort in Switzerland. The standard rate (about $500/night) got me an upgrade to a suite (about $1000/night), some fruit, and a half bottle of champagne. The way I see it, the amenities should be included anyway considering how much coin you're dropping on a room.

My experience was ruined because the hotel pretty much sucked (they couldn't even keep the lights on in the hallway for example -- with no button to push to turn them on either). I guess if you have the cash and stay at these places often enough it might be worth it, especially since some of them are not associated with any of the popular hotel programs (starwood, hilton, etc).

Overall the whole CB experience was disappointing. When I got my kidney stone in Austria I called them up to see if they could recommend a doctor or something but they were totally useless. Likewise, I never golf and I have no use for private jets. But then again, I'm under 40 and probably not in their target demographic.