I had forgotten how good this movie was until I got it on DVD.  Richard Dreyfuss puts in a great performance as Roy Neary.  His portrayal of the subtle changes his character goes through throughout the movie, from child like enthusiasm, to outright obsession, is spot on.  Francois Truffaut also puts in an outstanding performance.  This is the movie that established Spielberg's kind of "awe/woundrous" style of filmaking.  You know, like the spaceships in Close Encounters, E.T., Indiana Jones' adventures, the first glimpse of a dinosaur in the Jurassic series, he just stages some wonderfull awe inspiring scenes.