I was in Santiago at the Hyatt just up the street in Oct. '99, and they were just finishing up the Marriott. Looked quite impressive, entire structure looked too large for the number of rooms (~260 or something). The area is not downtown Santiago, but is a very upscale suburb. I loved it, lots to do in the city, it is very European...wide boulevards, lovely landscaping and gardens. Make sure to take the 1/2 day tour to Valparaiso -- beautiful drive.

Have fun!