I go from US to the Hilton Buenos Aires at least once a month and if I remember correctly they are building a Hilton Residence Buenos Aires or something like that for 2002. I will inquire on my next travels there about 2002.
I don't think the hotels in Buenos Aires want to re-affiliate in light of the poor economy down there. One interesting to note is that the Hilton Buenos Aires never seems to be fully-booked or even 40-60% full. Wonderful for me. The Hilton Buenos Aires is a great place.