These aren't my own thoughts -- they've come up in a discussion of _Flowers for Algernon_ which I read somewhere and don't seem to be able to cite now. In _Flowers_, the author gives momentum to his eventually super-intelligent protagonist by starting off with severe mental handicapping, then spending a majority of the story at normal intelligence before allowing us to imagine his next state. It is a great writing technique, giving direction and then leaving things to the imagination. Imagination is like a variable that scales the amazingness to fit each reader. I think movies often fail to leave enough space for imagination -- when they're left spelling everything out to the least imaginative member of the audience they leave everyone feeling limited and dissatisfied, glum.
If you want upbeat AI Sci Fi, read a book. Read Banks's _Culture_ series, James P. Hogan's _Two Faces of Tomorrow_, or in a gentler vein, Bradbury's _I Sing the Body Electric_.