Just back from 2 stays at the Amman Sheraton. Overall, I was very, very impressed and would happily go back.
We were upgraded to a junior suite on the Towers Floor both times (Plat member) and the new European amenity was offered without fuss. Should anyone be interested, the local gift is a pack of Dead Sea treatments. The junior suites are nicely set up - not super luxurious but very comfortable. The Towers lounge offers a decent breakfast buffet with hot and cold choices, along with a drinks from 5.30-7.30. Not bad for USD85 per night.
The staff are very friendly in the best traditions of Middle Eastern hospitality though things can get a little bit chaotic when busy - also in line with Middle Eastern tradition. The hotel was surprisingly busy - mostly with Americans enroute to or from Baghdad. The location is pretty good for the upmarket areas of Sheimeishani and Abdoun. It is a bit further into Downtown but taxis are super cheap - no more than USD3.