I think you were right Gaucho in refering to the Sushi places as more of an abmient than top cuisine.. there was another place I went to in Palermo (not Palermo Hollywood) that was a small family run sushi place that was fantastic.. (better than the one in Puerto Madero or Palermo Hollywood).. it was on a street paralel to St. Fe off Coronel Diaz.. ...
In terms of cusine.. the pasta mom & pop restaurants.. (ones inside residental areas) are fantastic and definetly worth trying a few... and don't forget to stop by the local Persicco for authentic Gelato...... it's by one of the Original Freddo founders (what used to be the bar of Gelato) until the over-franchised it... though there's also Munchi's (more expensive and overall good) and another one that opened on Avenida Libertador.. (I forgot the name but it's close the Paseo Alcorta shopping mall)...
Gaucho, by all means state your views as some of my aspects come more from socializing aspect of the 13 months I spent there.. ^